Plasma Clearance Rate Research Articles

Discovery of biophysical rate laws from the electronic health record enables real-time liver injury estimation from transaminase dynamics.

Alanine (ALT) and aspartate (AST) aminotransferases are standard-of-care biomarkers for liver injury though their temporal dynamics during injury and resolution remain incompletely characterized. Here, we analyze aminotransferase kinetics to determine whether rate laws can be ascertained during acute liver injury agnostic to etiology. From 6.5 million AST and ALT measurements in 91,086 patients, we identify a single rate-limiting step in transaminase decline enabling the discovery of plasma clearance rates of AST (1.13days-1) and ALT (0.47days-1). These rates highlight that transaminases lag real-time liver injury on timescales relevant to clinical decision-making. To resolve this delay, we introduce a correction for AST and ALT, the hepatocyte injury index (HIX, hix.massgeneral.org), which yields a real-time estimate of liver injury. For both liver biopsies and choledocholithiasis, the HIX better distinguishes persistent versus resolved liver injury than transaminase values alone. The HIX can enable more timely clinical decisions for patients with acute liver injury.

Subacute Toxicity and Pharmacokinetic Evaluation of the Synthetic Cannabinoid 4F-MDMB-BUTINACA in Rats: A Forensic and Toxicological Perspective

Background: 4-MDMB-BUTINACA, a next-generation synthetic cannabinoid, presents significant public health and forensic challenges due to its evolving nature and potential toxicity. Methods: This study evaluates the subacute toxic effects and pharmacokinetics of 4−Fluoro MDMB−BUTINACA (4F-MDMB-BUTINACA) in adult male albino rats, administered orally for seven days at doses of 1 mg/kg, 5 mg/kg, and 15 mg/kg. The hematological, biochemical, and histopathological parameters were assessed and compared to controls. Results: The pharmacokinetics were determined using GC–MS/MS with a positive chemical ionization and granisetron as an internal standard. A histological analysis revealed inflammatory cell aggregation, congestion, hemorrhage, edema, and fibrosis in various tissues, with renal examinations showing tubule degradation, glomerular atrophy, Bowman’s space expansion, edema, and hemorrhage. The liver exhibited cellular infiltration, while cardiac muscle fibers showed myocardial fiber degradation and inflammatory cell aggregation. Biochemical assays indicated significant alterations (p < 0.05) in the serum levels of AST, ALT, ALP, GGT, total protein, albumin, triglycerides, urea, MCHC, MCV, RDW, platelets, neutrophils, eosinophils, and basophils compared to the controls. Conclusions: The validated bioanalytical method revealed rapid absorption of 4F-MDMB-BUTINACA, with a plasma half-life of 2.371 h, a volume of distribution of 2272.85 L, and a plasma clearance rate of 664.241 L/h. In conclusion, 4F-MDMB-BUTINACA is a highly toxic synthetic cannabinoid, particularly affecting the liver, kidneys, and heart.

Discovery of orally bioavailable phosphonate prodrugs of potent ENPP1 inhibitors for cancer treatment

Ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1) is the dominant hydrolase of 2′,3′-cyclic GMP-AMP (cGAMP). Inhibition of ENPP1 contributes to increased cGAMP concentration and stimulator of interferon gene (STING) activation, with the potential to boost immune response against cancer. ENPP1 is a promising therapeutic target in tumor immunotherapy. To date, orally bioavailable ENPP1 inhibitors with highly potent activity under physiological conditions have been rarely reported. Herein, we report our effort in the design and synthesis of two different series of ENPP1 inhibitors, and in the identification of a highly potent ENPP1 inhibitor 27 (IC50 = 1.2 nM at pH 7.5), which significantly enhanced the cGAMP-mediated STING activity in THP-1 cells. Phosphonate compound 27 has good preclinical pharmacokinetic profiles with low plasma clearance rate in mouse, rat, and dog. It has been developed as bis-POM prodrug 36 which successfully improves the oral bioavailability of 27. In the Pan02 syngeneic mouse model of pancreatic cancer, orally administered 36 showed synergistic effect in combination with radiotherapy.

Predictability of combining Technetium-99m-galactosyl human serum albumin single-photon emission computed tomography/computed tomography and indocyanine green clearance test for posthepatectomy liver failure

PurposeTo evaluate the predictive ability of combining Technetium-99m-galactosyl human serum albumin (99mTc‑GSA) single-photon emission computed tomography (SPECT)/computed tomography (CT) volume and plasma clearance rate of indocyanine green (ICGK) for posthepatectomy liver failure (PHLF).Materials and methodsFifty patients who underwent 99mTc-GSA scintigraphy as a preoperative examination for segmentectomy or more from July 2021 to June 2023 were evaluated prospectively. Patients were divided into two groups according to the presence or absence of posthepatectomy liver failure (PHLF). Total functional liver volume (t-FLV) and remnant FLV (r-FLV) were measured from 99mTc-GSA SPECT/CT image. Future liver remnant ICGK (ICGK-F) was calculated by ICGK and remnant liver volume from CT. Area under the curve (AUC) of ICGK-F, r-FLV, r-FLV/t-FLV, ICGK × r-FLV, ICGK × r-FLV/t-FLV was calculated to evaluate predictive ability of each parameter for PHLF.ResultsPHLF was occurred in 7 patients. AUC of ICGK × r-FLV was significantly higher than that of ICGK-F (0.99; 95% confidence interval [CI]: 0.96–1 vs 0.82; 95%CI: 0.64–0.96; p = 0.036). There was no significant difference between the AUC of r-FLV, r-FLV/t-FLV, ICGK × r-FLV/t-FLV and that of ICGK-F, respectively.ConclusionThe combination of 99mTc‑GSA SPECT/CT volume and ICGK can predict PHLF more accurately than ICGK-F.

Self-Assembled Nanoparticles from Xie-Bai-San Decoction: Isolation, Characterization and Enhancing Oral Bioavailability.

Natural nanoparticles have been found to exist in traditional Chinese medicine (TCM) decoctions. However, whether natural nanoparticles can influence the oral bioavailability of active compounds has not been elucidated. Using Xie-Bai-San decoction (XBSD) as an example, the purpose of this study was to isolate, characterize and elucidate the mechanism of the nanoparticles (N-XBSD) in XBSD, and further to explore whether the bioavailability of the main active compounds could be enhanced by N-XBSD. N-XBSD were isolated from XBSD, and investigated its characterization and study of its formation mechanism, and evaluation of its ability to enhance bioavailability of active compounds. The N-XBSD was successfully isolated with the average particle size of 104.53 nm, PDI of 0.27 and zeta potential of -5.14 mV. Meanwhile, all the eight active compounds were most presented in N-XBSD. Kukoamine B could self-assemble with mulberroside A or liquiritin to form nanoparticles, respectively. And the FT-IR and HRMS results indicated the possible binding of the ammonium group of kukoamine B with the phenolic hydroxyl group of mulberroside A or liquiritin, respectively. The established UPLC-MS/MS method was accurate and reliable and met the quantitative requirements. The pharmacokinetic behaviors of the N-XBSD and decoction were similar in rats. Most notably, compared to that of free drugs, the Cmax, AUC0-∞, AUC0-t, T1/2 and MRT0-∞ values of index compounds were the higher in N-XBSD, with a slower plasma clearance rate in rats. The major active compounds of XBSD were mainly distributed in N-XBSD, and N-XBSD was formed through self-assembly among active compounds. N-XBSD could obviously promote the bioavailability of active compounds, indicating natural nanoparticles of decoctions play an important role in therapeutic effects.

Very-low-density lipoprotein triglyceride and free fatty acid plasma kinetics in women with high or low brown adipose tissue volume and overweight/obesity

Although a high amount of brown adipose tissue (BAT) is associated with low plasma triglyceride concentration, the mechanism responsible for this relationship in people is not clear. Here, we evaluate the interrelationships among BAT, very-low-density lipoprotein triglyceride (VLDL-TG), and free fatty acid (FFA) plasma kinetics during thermoneutrality in women with overweight/obesity who had a low (<20mL) or high (≥20mL) volume of cold-activated BAT (assessed by using positron emission tomography in conjunction with 2-deoxy-2-[18F]-fluoro-glucose). We find that plasma TG and FFA concentrations are lower and VLDL-TG and FFA plasma clearance rates are faster in women with high BAT than low BAT volume, whereas VLDL-TG and FFA appearance rates in plasma are not different between the two groups. These findings demonstrate that women with high BAT volume have lower plasma TG and FFA concentrations than women with low BAT volumes because of increased VLDL-TG and FFA clearance rates. This study was registered at ClinicalTrials.gov (NCT02786251).

Preparation scheme and research progress of GPCR antibody drugs

As a class of proteins that play crucial roles in physiological and pathological processes within the human body, G protein-coupled receptors (GPCRs) have emerged as prominent targets for drug development. However, there is still ample room for improvement and replacement of currently developed drugs due to their inherent toxicity and associated side effects. In recent years, the attention has shifted towards antibody-based therapeutics targeting GPCRs, owing to their exceptional specificity and low plasma clearance rate. This review provides an overview of the fundamental preparation process and existing challenges encountered in developing GPCR antibody drugs, along with an introduction to several strategies employed in their formulation.

Liver remnant volume to body weight ratio of 0.65% as a lower limit in right hepatic trisectionectomy with bile duct resection

BackgroundPrevious studies have suggested the utility of an indocyanine green plasma clearance rate of the future liver remnant (FLR) (ICGK-F) ≥0.05 in hepatobiliary resection to reduce the surgical risk. The present study aimed to verify whether future liver remnant size rather than ICGK-F matters in extended hepatobiliary resection. MethodsBetween 2004 and 2021, patients who underwent right hepatic trisectionectomy with bile duct resection were included. The effect of the FLR volume-to-body weight ratio (FLR/BW) and ICGK-F on posthepatectomy liver failure was evaluated along with other parameters. ResultsAmong 91 study patients, the median ICGK-F, FLR, and FLR/BW were 0.057 (range, 0.027–0.099), 392 mL (145–705), and 0.78% (0.40–1.37), respectively. Posthepatectomy liver failure occurred in 23 patients. The incidence was 10 (40%) in 25 patients with an ICGK-F <0.05 and 12 (18%) in 65 patients with an ICGK-F ≥0.05 (P = .053); 13 (52%) in 25 patients with a FLR/BW <0.65% and 10 (15%) in 66 patients with a FLR/BW ≥0.65% (P = .001). Multivariate analysis showed that a FLR/BW <0.65% (odds ratio, 11.7; P = .005), age ≥65 years (odds ratio, 31.7; P < .001), and blood loss ≥25 mL/kg (odds ratio, 22.1; P = .004) were independent predictors of posthepatectomy liver failure, but ICGK-F <0.05 was not (P = .499). According to the meeting number of 3 factors, posthepatectomy liver failure incidence was 0 of 22 (0%) in patients with 0 factors, 6 of 43 (14%) in patients with 1, and 17 of 26 (65%) in patients with 2 or 3 (P < .001). ConclusionA FLR/BW ≥0.65% may serve as a volumetric basis to reduce posthepatectomy liver failure after extended hepatobiliary resection.

A Rapid and Sensitive UPLC-MS/MS Method for the Determination of Bellidifolin and Pharmacokinetics Study of Bellidifolin Nano-microcells

Background: Bellidifolin (BEL) has a decent enemy of myocardial fibrosis impact, and its preparation into nano-micelles can build security and great biocompatibility in vitro and in vivo. The pharmacokinetic assessment of BEL can be utilized as the reason for the security and viability of BEL in clinical use. Objective: This research aimed to establish an effective UPLC-MS/MS strategy for assuring BEL in rodent plasma and concentrating on its pharmacokinetics in vivo. Methods: Luteolin was utilized as an internal standard (IS). Chromatographic separation was accomplished utilizing a UPLC HSS T3 column (2.1 ×100 mm, 1.8 μm) section using a mobile phase of 0.1% acetonitrile (A) and 0.1% formic acid in water (B) with gradient elution. Electrospray ionization (ESI) coupled mass spectrometry was applied in various response checking (MRM) modes with negative ionization. Results: The pharmacokinetic behaviour of bellidifolin nano-micelles in vivo showed that the peak concentration (Cmax) was 1666.19±479.92 μg/L, the time to peak (Tmax) was 0.167 h, and the apparent elimination half-life (t1/2) was 7.60±3.58 h. The plasma clearance rate (CL/F) was 1.15±0.48 L/h/kg, the apparent volume of distribution (V/F) was 14.38±11.04, the area under the curve (AUC) was 8292.57±4193.13 μg/L*h, and the mean retention time (MRT) was 9.70±4.55 h. Conclusion: The method was successfully applied to the plasma pharmacokinetics of bellidifolin nano-micelles after intragastric administration to rats.

A Metabolomics study of metabolites associated with the glomerular filtration rate

BackgroundChronic kidney disease (CKD) is a global public health issue. The diagnosis of CKD would be considerably enhanced by discovering novel biomarkers used to determine the glomerular filtration rate (GFR). Small molecule metabolites related to kidney filtration function that might be utilized as biomarkers to measure GFR more accurately could be found via a metabolomics analysis of blood samples taken from individuals with varied glomerular filtration rates.MethodsAn untargeted metabolomics study of 145 plasma samples was performed using ultrahigh-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS). The 145 samples were divided into four groups based on the patient’s measured glomerular filtration rates (mGFRs) determined by the iohexol plasma clearance rate. The data were analyzed using random forest analyses and six other unique statistical analyses. Principal component analysis (PCA) was conducted using R software.ResultsA large number of metabolites involved in various metabolic pathways changed significantly between groups with different GFRs. These included metabolites involved in tryptophan or pyrimidine metabolism. The top 30 metabolites that best distinguished between the four groups in a random forest plot analysis included 13 amino acids, 9 nucleotides, and 3 carbohydrates. A panel of metabolites (including hydroxyaparagine, pseudouridine, C-glycosyltryptophan, erythronate, N-acetylalanine, and 7-methylguanidine) for estimating GFR was selected for future testing in targeted analyses by combining the candidate lists with the six other statistical analyses. Both hydroxyasparagine and N,N-dimethyl-proline-proline are unique biomarkers shown to be inversely associated with kidney function that have not been reported previously. In contrast, 1,5-anhydroglucitol (1,5-AG) decreases with impaired renal function.ConclusionsThis global untargeted metabolomics study of plasma samples from patients with different degrees of renal function identified potential metabolite biomarkers related to kidney filtration. These novel potential metabolites provide more insight into the underlying pathophysiologic processes that may contribute to the progression of CKD, lead to improvements in the estimation of GFR and provide potential therapeutic targets to improve kidney function.

CytoSorb hemoperfusion markedly attenuates circulating cytokine concentrations during systemic inflammation in humans in vivo

BackgroundThe CytoSorb hemoadsorption device has been demonstrated to be capable of clearing inflammatory cytokines, but has not yet been shown to attenuate plasma cytokine concentrations. We investigated the effects of CytoSorb hemoperfusion on plasma levels of various cytokines using the repeated human experimental endotoxemia model, a highly standardized and reproducible human in vivo model of systemic inflammation and immunological tolerance induced by administration of bacterial lipopolysaccharide (LPS).MethodsTwenty-four healthy male volunteers (age 18–35) were intravenously challenged with LPS (a bolus of 1 ng/kg followed by continuous infusion of 0.5 ng/kg/hr for three hours) twice: on day 0 to quantify the initial cytokine response and on day 7 to quantify the degree of endotoxin tolerance. Subjects either received CytoSorb hemoperfusion during the first LPS challenge (CytoSorb group), or no intervention (control group). Plasma cytokine concentrations and clearance rates were determined serially. This study was registered at ClinicalTrials.gov (NCT04643639, date of registration November 24th 2020).ResultsLPS administration led to a profound increase in plasma cytokine concentrations during both LPS challenge days. Compared to the control group, significantly lower plasma levels of tumor necrosis factor (TNF, − 58%, p < 0.0001), interleukin (IL)-6 ( − 71%, p = 0.003), IL-8 ( − 48%, p = 0.02) and IL-10 ( − 26%, p = 0.03) were observed in the CytoSorb group during the first LPS challenge. No differences in cytokine responses were observed during the second LPS challenge.ConclusionsCytoSorb hemoperfusion effectively attenuates circulating cytokine concentrations during systemic inflammation in humans in vivo, whereas it does not affect long-term immune function. Therefore, CytoSorb therapy may be of benefit in conditions characterized by excessive cytokine release.

Rosemary and CoQ10 Alleviated the Detrimental Effects of Concomitant Administration of Acetaminophen and Carbamazepine by Accelerating Their Metabolism and Elimination

BACKGROUND: The interaction of carbamazepine (CBZ) and acetaminophen (APAP) could result in hepatic failure and mortality. This study was conducted to analyzed the potential of rosemary ethanol extract (REE) or coenzyme Q10 (CoQ10) to alleviate the interactions between CBZ and APAP.METHODS: Fourty-eight adult male rats were treated differently based on the assigned groups. Oxidative stress parameters, including malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase, and glutathione S-transferase (GST), and the expression levels of CYP3A4, CYP2E1, IL-6, TNF-α, and IL-1B in the liver were estimated. In addition, the histopathology of liver was examined and the plasma clearance rate of CBZ and APAP was estimated.RESULTS: Combination of CBZ and APAP significantly elevated alanine aminotransferase (ALT) activity and hepatic MDA, and reduced the activities of GPx, GST, and GSH level in liver. The gene expression of CYP3A4 and CYP2E1 was upregulated by CBZ and CoQ10, respectively. The expression of IL-6 has decreased in the groups treated with CBZ alone or in combination with APAP. TNF-α expression was significantly downregulated in the groups treated with CBZ, APAP, REE, CoQ10, or combination CBZ and APAP. The liver from CBZ and APAP combination group showed centrolobular degeneration and necrosis. REE and CoQ10 were able to alleviate most of these detrimental effects. The combined administration of CBZ and APAP extended the plasma clearance time of APAP and CBZ from 6 to 24 and from 9 to 24 hours, respectively.CONCLUSION: REE and CoQ10 alleviated the detrimental effects of the combination of CBZ and APAP through enhancing the cellular antioxidant milieu, induction of metabolizing enzymes, reduction of the plasma half-life of APAP and CBZ preventing their accumulation and potential interaction.KEYWORDS: acetaminophen, antioxidants, carbamazepine, CoQ10, CYP3A4, CYP2E1, glutathione, lipid peroxidation, rosemary

Indocyanine green plasma clearance rate and 99mTc-galactosyl human serum albumin single-photon emission computed tomography evaluated preoperative remnant liver.

BACKGROUNDPreoperative evaluation of future remnant liver reserves is important for safe hepatectomy. If the remnant is small, preoperative portal vein embolization (PVE) is useful. Liver volume analysis has been the primary method of preoperative evaluation, although functional examination may be more accurate. We have used the functional evaluation liver using the indocyanine green plasma clearance rate (KICG) and 99mTc-galactosyl human serum albumin single-photon emission computed tomography (99mTc-GSA SPECT) for safe hepatectomy.AIMTo analyze the safety of our institution’s system for evaluating the remnant liver reserve.METHODSWe retrospectively reviewed the records of 23 patients who underwent preoperative PVE. Two types of remnant liver KICG were defined as follows: Anatomical volume remnant KICG (a-rem-KICG), determined as the remnant liver anatomical volume rate × KICG; and functional volume remnant KICG (f-rem-KICG), determined as the remnant liver functional volume rate based on 99mTc-GSA SPECT × KICG. If either of the remnant liver KICGs were > 0.05, a hepatectomy was performed. Perioperative factors were analyzed. We defined the marginal group as patients with a-rem-KICG of < 0.05 and a f-rem-KICG of > 0.05 and compared the postoperative outcomes between the marginal and not marginal (both a-rem-KICG and f-rem-KICG > 0.05) groups.RESULTSAll 23 patients underwent planned hepatectomies. Right hepatectomy, right trisectionectomy and left trisectionectomy were in 16, 6 and 1 cases, respectively. The mean of blood loss and operative time were 576 mL and 474 min, respectively. The increased amount of f-rem-KICG was significantly larger than that of a-rem-KICG after PVE (0.034 vs 0.012, P = 0.0273). The not marginal and marginal groups had 17 (73.9%) and 6 (26.1%) patients, respectively. The complications of Clavian-Dindo classification grade II or higher and post-hepatectomy liver failure were observed in six (26.1%) and one (grade A, 4.3%) patient, respectively. The 90-d mortality was zero. The marginal group had no significant difference in postoperative outcomes (prothrombin time/international normalised ratio, total bilirubin, complication, post-hepatectomy liver failure, hospital stay, 90-d, and mortality) compared with the not-marginal group.CONCLUSIONFunctional evaluation of the remnant liver enabled safe hepatectomy and may extend the indication for hepatectomy after PVE treatment.

Physiological interindividual variability in endogenous estradiol concentration does not influence adipose tissue and hepatic lipid kinetics in women.

Increased triglyceride (TG) and apolipoprotein B-100 (apoB-100) concentrations in plasma are important risk factors for cardiovascular disease in women. Administration of some estrogen preparations raises plasma TG and apoB-100 concentrations by increasing hepatic very low-density lipoprotein (VLDL) TG and apoB-100 secretion rates. However, the influence of physiological variation in endogenous estradiol on VLDL-TG and VLDL-apoB-100 metabolism and on free fatty acid (FFA) release into plasma (the major source of fatty acids for VLDL-TG production) is not known. We measured basal VLDL-TG, VLDL-apoB-100, and plasma FFA kinetics by using stable isotopically labeled tracers in 36 eumenorrheic, premenopausal women (age: 33 ± 2 years, BMI: 31 ± 1 kg/m2; mean ± s.e.m.) during the follicular phase of the menstrual cycle; participants were divided into two groups based on low (n = 18) or high (n = 18) plasma estradiol concentrations (defined as below or above the median value of 140 pmol/L in the whole group). Mean plasma estradiol concentration was >3-fold higher in the high-estradiol than in the low-estradiol group (299 ± 37 and 96 ± 7 pmol/L, P < 0.001); there was no difference in plasma progesterone concentrations between the two groups (P = 0.976). There were no significant differences in plasma FFA concentration, FFA rate of appearance in plasma, VLDL-TG and VLDL-apoB-100 concentrations, hepatic VLDL-TG and VLDL-apoB-100 secretion rates, VLDL-TG and VLDL-apoB-100 plasma clearance rates, and mean residence times (all P ≥ 0.45). No significant associations were found between plasma estradiol concentration and FFA, VLDL-TG, and VLDL-apoB-100 concentrations and kinetics (all P > 0.19). Plasma estradiol concentration is not an important correlate of basal plasma FFA, VLDL-TG, and VLDL-apoB-100 kinetics in premenopausal women.

HPLC-MS/MS analysis of primary alkaloids in rat plasma after oral administration of “Nux vomica - Glycyrrhiza glabra decoction”: A pharmacokinetic study

Ethnopharmacological relevanceDecoction is the most common form of administering traditional Chinese medicine (TCM). During the preparation of decoction, the high temperature and complex chemical environment result in the formation of complex and multiple phases. The differences in drug components in different phases induce gastrointestinal absorption and physiological response. Nux vomica (Strychnos nux-vomica L) is a typical toxic TCM used in China, with remarkable pharmacological activity. In order to reduce its toxicity, nux vomica (NV) is often decocted with Glycyrrhiza glabra (GG) in clinic, and the detoxification mechanism has always been the focus of research interest. Most studies investigated the compatibility of NV-GG, but the in vivo behavior of individual constituents based on phase state has yet to be elucidated. Aim of the studyTo investigate the pharmacokinetic behavior of typical toxic components in different phase states of “NV-GG decoction” in rat plasma. Materials and methodsThe sediment, suspension, colloid and true solution of “NV-GG decoction” was obtained via physical methods. The main components in different phase states were analyzed via reliable UFLC-Q-TOF-MS high-resolution mass spectrometry. A rapid and accurate HPLC-qqq-MS/MS method was established and validated for accurate determination of brucine and strychnine levels in plasma, followed by pharmacokinetic evaluation of different phase states of “NV-GG decoction” in rats. Kinetex F5 100A (50 mm × 3.0 mm, 2.6 μm) column was used for chromatographic separation. Aqueous solution containing acetonitrile and 0.1% formic acid was used as the mobile phase, followed by gradient elution at 0.4 mL/min. Mass spectra were detected by electrospray ionization (ESI) multiple reaction monitoring (MRM) in positive ion mode. ResultsFifteen different alkaloids were detected in different phase states of “NV-GG decoction”. Strychnine and brucine, which are toxic components with high content, were selected for quantitative analysis. The established UPLC-qqq-MS/MS method is accurate and reliable with a good linearity (R2 > 0.99) in the respective concentration range, satisfying the quantitative requirements. The pharmacokinetic parameters of different phase states of rats differed significantly after gavage. The deposition phase was the most prominent. The index components showed higher Cmax, AUC0 and Tmax, while the T1/2, MRT, V/F and CL/F were the smallest, with a relatively slow plasma clearance rate in rats. The true solution group showed the lowest Tmax and the fastest absorption. ConclusionThis method has been successfully utilized to study the pharmacokinetics of different phase states of “NV-GG decoction”. Among the four phases, the deposition phase contributed to a large proportion of the in vivo kinetic behavior similar to that of sustained-release preparations, with slow absorption of toxic components and prolonged peak time. The pharmacokinetic parameters and plasma concentration-time curves of each phase can be used to study toxicity reduction of NV-GG and increase its biocompatibility.

Criticality of Surface Characteristics of Intravenous Iron-Carbohydrate Nanoparticle Complexes: Implications for Pharmacokinetics and Pharmacodynamics.

Un-complexed polynuclear ferric oxyhydroxide cannot be administered safely or effectively to patients. When polynuclear iron cores are formed with carbohydrates of various structures, stable complexes with surface carbohydrates driven by multiple interacting sites and forces are formed. These complexes deliver iron in a usable form to the body while avoiding the serious adverse effects of un-complexed forms of iron, such as polynuclear ferric oxyhydroxide. The rate and extent of plasma clearance and tissue biodistribution is variable among the commercially available iron–carbohydrate complexes and is driven principally by the surface characteristics of the complexes which dictate macrophage opsonization. The surface chemistry differences between the iron–carbohydrate complexes results in significant differences in in vivo pharmacokinetic and pharmacodynamic profiles as well as adverse event profiles, demonstrating that the entire iron–carbohydrate complex furnishes the pharmacologic action for these complex products. Currently available physicochemical characterization methods have limitations in biorelevant matrices resulting in challenges in defining critical quality attributes for surface characteristics for this class of complex nanomedicines.

Tumor-targeted hyaluronic acid-mPEG modified nanostructured lipid carriers for cantharidin delivery: An in vivo and in vitro study

AimCantharidin (CTD), the major component of the anti-cancer medicine obtained from Mylabris cichorii, exerts good inhibitory effects on several cancers, such as liver and breast cancer. However, owing to its toxicity, its oral administration can cause various adverse effects, limiting its clinical applications. Therefore, the development of a novel nano-drug delivery system for CTD would be highly beneficial. MethodsA nanostructured lipid carrier (NLC) was designed to actively target CTD to tumor cells using a hyaluronic acid (HA)-decorated copolymer (mPEG-NH2); the NLCs were called HA-mPEG-CTD-NLC. HA-mPEG was synthesized using amidation, and HA-mPEG-CTD-NLC was generated through ultrasonic emulsification in water. The mean hydrodynamic diameter of the particles was approximately 119.3 nm. ResultsPharmacokinetic studies revealed that the half-life of HA-mPEG-CTD-NLC and its area under the curve were higher than those of a CTD solution. Further, the plasma clearance rate of HA-mPEG-CTD-NLC was 0.41 times that of the CTD solution, implying a significantly prolonged drug retention time in vivo. Fluorescence in vivo endo-microscopy and optical in vivo imaging revealed that HA-mPEG-CTD-NLC had superior cytotoxicity and targeting efficacy against SMMC-7721 cells. An evaluation of the in vivo anti-tumor activity showed that HA-mPEG-CTD-NLC significantly inhibited tumor growth and prolonged survival in tumor-bearing mice, with a tumor inhibition rate of 65.96%. ConclusionsOur results indicate that HA-mPEG-CTD-NLC may have great potential in liver cancer-targeted therapy.

Abstract MP30: Excess HDL Free Cholesterol Bioavailability Drives Free Cholesterol Accretion Into Macrophages And Erythrocytes In Scarb1 -/- Mice

Aim: In humans, very high plasma HDL-cholesterol concentrations are associated with increased all cause- and atherosclerotic cardiovascular disease (ASCVD)-mortality. The HDL receptor-deficient mouse (Scarb1 -/- ), a robust model of this phenotype, is characterized by high free cholesterol (FC) bioavailability due to too many HDL particles that are FC-rich. Clinically, plasma LDL and HDL are quantified according to total cholesterol content, the sum of FC and esterified cholesterol, which likely contribute to ASCVD pathophysiology differently. A Western diet induces ASCVD in Scarb1 -/- mice, despite an attendant increase in HDL. We tested the hypothesis that high HDL-FC bioavailability contributes to ASCVD in Scarb1 -/- mice by increasing FC flux into macrophage cells, erythrocytes and other major tissues. Methods: Influx of HDL-FC and efflux of macrophage FC were determined between WT and Scarb1 -/- HDL and J774 macrophage cells. HDL of both genotypes were radiolabelled with [ 3 H]FC, injected into autologous mice, and the rates of plasma clearance and erythrocyte uptake were determined. Results: The magnitude of FC transfer from Scarb1 -/- HDL to LDL is greater than that from WT HDL; APOB-containing lipoproteins from Scarb1 -/- vs. WT mice are FC-enriched due likely to greater HDL-FC transfer. While macrophage efflux to HDL of Scarb1 -/- vs. WT HDL was not different, FC influx from Scarb1 -/- vs. WT HDL to macrophages was three-fold greater, a net effect that increased the FC burden of macrophages. In vivo studies showed that compared to WT mice, in Scarb1 -/- mice, autologous HDL-FC cleared more slowly and more FC transferred to erythrocytes. We compared the FC, CE, PL, and TG contents of all major tissues and determined that FC accretion by some tissues is higher among Scarb1 -/- vs. WT mice whereas in other tissues FC homeostasis is maintained. Lastly, we determined that the tissue compositions and plasma FC clearance kinetics varied according to sex, particularly among Scarb1 -/- mice. Conclusions: These findings are relevant to pathologies specific to Scarb1 -/- mice and to the evolving model of the role of HDL-FC in RCT. They provide a rationale for human studies to determine the utility of HDL-FC bioavailability as a risk factor for ASCVD and other pathologies.

Bleomycin Concentration in Patients’ Plasma and Tumors after Electrochemotherapy. A Study from InspECT Group

The plasma concentration profile of bleomycin in the distribution phase of patients younger than 65 years is needed to determine the suitable time interval for efficient application of electric pulses during electrochemotherapy. Additionally, bleomycin concentrations in the treated tumors for effective tumor response are not known. In this study, the pharmacokinetic profile of bleomycin in the distribution phase in 12 patients younger than 65 years was determined. In 17 patients, the intratumoral bleomycin concentration was determined before the application of electric pulses. In younger patients, the pharmacokinetics of intravenously injected bleomycin demonstrated a faster plasma clearance rate than that in patients older than 65 years. This outcome might indicate that the lowering of the standard bleomycin dose of 15,000 IU/m2 with intravenous bleomycin injection for electrochemotherapy is not recommended in younger patients. Based on the plasma concentration data gathered, a time interval for electrochemotherapy of 5–15 min after bleomycin injection was determined. The median bleomycin concentration in tumors 8 min after bleomycin injection, at the time of electroporation, was 170 ng/g. Based on collected data, the reduction of the bleomycin dose is not recommended in younger patients; however, a shortened time interval for application of electric pulses in electrochemotherapy to 5–15 min after intravenous bleomycin injection should be considered.

Toward New Transmission-Blocking Combination Therapies: Pharmacokinetics of 10-Amino-Artemisinins and 11-Aza-Artemisinin and Comparison with Dihydroartemisinin and Artemether.

ABSTRACTAs artemisinin combination therapies (ACTs) are compromised by resistance, we are evaluating triple combination therapies (TACTs) comprising an amino-artemisinin, a redox drug, and a third drug with a different mode of action. Thus, here we briefly review efficacy data on artemisone, artemiside, other amino-artemisinins, and 11-aza-artemisinin and conduct absorption, distribution, and metabolism and excretion (ADME) profiling in vitro and pharmacokinetic (PK) profiling in vivo via intravenous (i.v.) and oral (p.o.) administration to mice. The sulfamide derivative has a notably long murine microsomal half-life (t1/2 > 150 min), low intrinsic liver clearance and total plasma clearance rates (CLint 189.4, CLtot 32.2 ml/min/kg), and high relative bioavailability (F = 59%). Kinetics are somewhat similar for 11-aza-artemisinin (t1/2 > 150 min, CLint = 576.9, CLtot = 75.0 ml/min/kg), although bioavailability is lower (F = 14%). In contrast, artemether is rapidly metabolized to dihydroartemisinin (DHA) (t1/2 = 17.4 min) and eliminated (CLint = 855.0, CLtot = 119.7 ml/min/kg) and has low oral bioavailability (F) of 2%. While artemisone displays low t1/2 of <10 min and high CLint of 302.1, it displays a low CLtot of 42.3 ml/min/kg and moderate bioavailability (F) of 32%. Its active metabolite M1 displays a much-improved t1/2 of >150 min and a reduced CLint of 37.4 ml/min/kg. Artemiside has t1/2 of 12.4 min, CLint of 673.9, and CLtot of 129.7 ml/kg/min, likely a reflection of its surprisingly rapid metabolism to artemisone, reported here for the first time. DHA is not formed from any amino-artemisinin. Overall, the efficacy and PK data strongly support the development of selected amino-artemisinins as components of new TACTs.