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Drug Metabolism and Pharmacokinetics Apr 2023P-glycoprotein (P-gp) expression in lymphocytes is variable and 2-fold higher in rheumatoid arthritis (RA) patients with treatment resistance than in healthy subjects....
P-glycoprotein (P-gp) expression in lymphocytes is variable and 2-fold higher in rheumatoid arthritis (RA) patients with treatment resistance than in healthy subjects. To date the information on P-gp-mediated drug interaction in lymphocyte is limited. We analyzed the importance on P-gp in lymphocytes using peripheral blood mononuclear cells (PBMCs) together with K562, K562/Adr, and K562/Vin cells, which have various P-gp levels, as cell models, and dexamethasone, nintedanib and apafant as weak to good P-gp substrates. P-gp levels in K562, K562/Adr, and K562/Vin cells were 0.3-, 20-, and 106-fold of healthy PBMCs, respectively. While cell accumulation of apafant and nintedanib decreased in all cells with increasing P-gp levels, dexamethasone accumulation in K562/Adr was comparable to that in healthy PBMCs and K562 cells. Cell accumulations of substrates in cells with low P-gp expression were not significantly changed by the P-gp inhibitors at therapeutic concentrations. However, accumulation increased to 1.4-fold at highest in K562/Adr cells with higher P-gp expression than in PBMCs of the RA patients. These results suggest P-gp controls the cellular concentration of P-gp substrates in PBMCs or K562 cells but cellular concentration of a weak P-gp substrate would not be apparently affected even in cells with a sufficient P-gp expression.
Topics: Humans; ATP Binding Cassette Transporter, Subfamily B, Member 1; K562 Cells; Drug Resistance, Multiple; Doxorubicin; Leukocytes, Mononuclear; Drug Resistance, Neoplasm; ATP Binding Cassette Transporter, Subfamily B; Dexamethasone
PubMed: 36724603
DOI: 10.1016/j.dmpk.2022.100487 -
Annals of Clinical and Laboratory... Sep 2020Analysis of P-Gp and TOPO II expression levels and their clinical significance in colon cancer.
OBJECTIVE
Analysis of P-Gp and TOPO II expression levels and their clinical significance in colon cancer.
METHODS
A total of 300 cases of paraffin embedded specimens of primary colon cancer were collected from the Affiliated Hospital of Putian University. The levels of P-Gp and TOPO II expression in colon cancer tissues were detected by the two-step En Vison.
RESULTS
P-glycoprotein (P-Gp) was mainly localized in the membrane and nucleus of colon cancer cells and the positive expression rate was 62% (186/300). The positive expression of P-Gp correlated with gender, invasion depth and lymph node metastasis and the differences were statistically significant (<0.05). Topoisomerase II (TOPO II) was mainly expressed in the cell nucleus and the positive rate was 83.3%. A total of 250 out of 300 samples were TOPO II positive and exhibited significant correlation with invasion depth, lymph node metastasis and differentiation degree (<0.05). Spearman correlation analysis indicated that P-Gp and TOPO II expression levels in colon cancer were positively correlated (r=0.480).
CONCLUSION
P-Gp and TOPO II expression levels were associated with colon cancer progression.
Topics: ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Adenocarcinoma; Adult; Aged; Aged, 80 and over; Antigens, Neoplasm; Cell Differentiation; China; Colonic Neoplasms; DNA Topoisomerases, Type II; Drug Resistance, Neoplasm; Female; Gene Expression; Gene Expression Regulation, Neoplastic; Glutathione S-Transferase pi; Humans; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Invasiveness; Stomach Neoplasms
PubMed: 33067204
DOI: No ID Found -
Veterinary Pathology Nov 2019P-glycoprotein (P-gp/ABCB1) and breast cancer resistance protein (BCRP/ABCG2) expression are frequently related to multidrug resistance (MDR) in neoplastic cells. Canine...
P-glycoprotein (P-gp/ABCB1) and breast cancer resistance protein (BCRP/ABCG2) expression are frequently related to multidrug resistance (MDR) in neoplastic cells. Canine inflammatory and grade III noninflammatory mammary carcinomas (IMC and non-IMC) are aggressive tumors that could benefit from chemotherapy. This study describes the immunohistochemical detection of P-gp and BCRP in 20 IMCs and 18 non-IMCs from dogs that had not received chemotherapy. Our aim was to determine if P-gp and BCRP expression was related to the "inflammatory" phenotype, to establish a basis for future studies analyzing the response to chemotherapy in dogs with highly malignant mammary cancer. Immunolabeling was primarily membranous for P-gp with a more intense labeling in emboli, and immunolabeling was membranous and cytoplasmic for BCRP. P-gp was expressed in 17 of 20 (85%) IMCs compared to 7 of 18 (39%) non-IMCs ( = 0.006). BCRP was expressed within emboli in 15 of 19 (79%) emboli in IMC, 12 of 15 (80%) primary IMCs, and 12 of 18 (67%) non-IMCs, without statistically significant differences ( > .05). All IMCs and 67% of non-IMCs expressed at least 1 of the 2 transporters, and 63% (12/19) of IMCs and 39% (7/18) of non-IMCs expressed both P-gp and BCRP. P-gp and BCRP evaluation might help select patients for chemotherapy. P-gp, expressed in a significantly higher percentage of IMCs vs non-IMCs, might play a specific role in the chemoresistance of IMC.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; ATP Binding Cassette Transporter, Subfamily G, Member 2; Animals; Dog Diseases; Dogs; Female; Gene Expression Regulation, Neoplastic; Immunohistochemistry; Mammary Neoplasms, Animal; Neoplasm Proteins; Phenotype
PubMed: 31526115
DOI: 10.1177/0300985819868647 -
Journal of Cerebral Blood Flow and... Jan 2020P-glycoprotein (P-gp, ABCB1) is an efflux transporter at the blood-brain barrier (BBB), which mediates clearance of beta-amyloid (Aβ) from brain into blood. We used...
P-glycoprotein (P-gp, ABCB1) is an efflux transporter at the blood-brain barrier (BBB), which mediates clearance of beta-amyloid (Aβ) from brain into blood. We used ()-[C]verapamil PET in combination with partial P-gp inhibition with tariquidar to measure cerebral P-gp function in a beta-amyloidosis mouse model (APPtg) and in control mice at three different ages (50, 200 and 380 days). Following tariquidar pre-treatment (4 mg/kg), whole brain-to-plasma radioactivity concentration ratios () were significantly higher in APPtg than in wild-type mice aged 50 days, pointing to decreased cerebral P-gp function. Moreover, we found an age-dependent decrease in cerebral P-gp function in both wild-type and APPtg mice of up to -50%. Alterations in P-gp function were more pronounced in Aβ-rich brain regions (hippocampus, cortex) than in a control region with negligible Aβ load (cerebellum). PET results were confirmed by immunohistochemical staining of P-gp in brain microvessels. Our results confirm previous findings of reduced P-gp function in Alzheimer's disease mouse models and show that our PET protocol possesses adequate sensitivity to measure these functional changes in vivo. Our PET protocol may find use in clinical studies to test the efficacy of drugs to induce P-gp function at the human BBB to enhance Aβ clearance.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Age Factors; Alzheimer Disease; Amyloidosis; Animals; Biological Transport; Blood-Brain Barrier; Brain Chemistry; Disease Models, Animal; Mice; Positron-Emission Tomography; Quinolines
PubMed: 30354871
DOI: 10.1177/0271678X18806640 -
Journal of Liposome Research Jun 2022The markedly low oral bioavailability of domperidone (anti-emetic drug) is associated with rapid first-pass metabolism in the intestine and liver. To counteract such...
The markedly low oral bioavailability of domperidone (anti-emetic drug) is associated with rapid first-pass metabolism in the intestine and liver. To counteract such affects, there is a need to devise a strategy to enhance absorption and subsequently bioavailability. Thus, the current study was aimed at synthesizing phytosomes consisting of phosphatidylcholine and piperine (a P-glycoprotein inhibitor). Phytosomes were prepared by salting-out method. The developed phytosomes were extensively characterized for size, zeta potential, polydispersity index, entrapment efficiency (EE %), infra-red spectroscopy, X-ray diffraction drug release, permeation, pharmacokinetic and toxicity. The engineered formulations of phytosomes with piperine exhibited a significant improvement in oral bioavailability of domperidone (79.5%) in comparison with the pure drug suspension under the same conditions. Pharmacokinetic parameters such as maximal plasma concentration (C) and the plasma concentration (estimated from area under the curve; AUC) of domperidone have been greatly increased relative to drug alone. The improved drug absorption was attributed to inhibition of P-glycoprotein transporter. The findings of current research work suggest that the optimized phytosomes based drug delivery containing phytochemicals as bioenhancers have the potential to improve bioavailability of poorly bioavailable drugs that are substrate to P-glycoprotein.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Administration, Oral; Alkaloids; Benzodioxoles; Biological Availability; Domperidone; Liposomes; Particle Size; Piperidines; Polyunsaturated Alkamides
PubMed: 33944662
DOI: 10.1080/08982104.2021.1918153 -
The Pharmacogenomics Journal Oct 2021Steroid remains the keystone therapy for Idiopathic Nephrotic Syndrome (NS). Besides genetic factors and histological changes, pharmacogenomic factors also affect the...
Steroid remains the keystone therapy for Idiopathic Nephrotic Syndrome (NS). Besides genetic factors and histological changes, pharmacogenomic factors also affect the steroid response. The upregulation of P-glycoprotein (P-gp) and Multidrug resistance-associated protein 1 (MRP-1) modulate the pharmacokinetics of steroids and may contribute to steroid resistance. Flow-cytometric analysis of P-gp, MRP-1 expression and functional activity on peripheral blood mononuclear cells (PBMCs) was carried out in steroid-sensitive nephrotic syndrome (SSNS) (n = 171, male 103, mean age = 8.54 ± 4.3); and steroid-resistant nephrotic syndrome (SRNS) (n = 83, male 43, mean age = 7.43 ± 4.6) patients. The genotypings of MDR-1 gene were carried out using PCR-RFLP. We observed that the percentage expression of P-gp (10.01 ± 2.09 and 3.79 ± 1.13, p < 0.001); and MRP-1 (15.91 ± 3.99 and 7.40 ± 2.33, p < 0.001) on lymphocyte gated population were significantly higher in SRNS than that of SSNS. The functional activity of P-gp and MRP-1 was also significantly escalated in SRNS as compared to SSNS (68.10 ± 13.35 and 28.93 ± 7.57, p < 0.001); (72.13 ± 8.34 and 31.56 ± 8.65, p < 0.001) respectively. AUC-ROC curve analysis revealed that P-gp and MRP-1 expression with a cut-off value of 7.13% and 9.62% predicted SRNS with the sensitivity of 90% and 80.7%; and specificity 90% and 80%, respectively. Moreover, MDR-1 homozygous mutant TT+AA for G2677T/A (rs2032582) was significantly associated with SRNS (p = 0.025, OR = 2.86 CI = 1.14-7.14). The expression of P-gp (9.68 ± 4.99 v/s 5.88 ± 3.38, p = 0.002) was significantly higher in the patients of homozygous mutant alleles compared to wildtype GG. The increased expression and functionality of P-gp and MRP-1 contribute to steroid resistance, and MDR-1 homozygous mutant G2677T/A promotes steroid resistance by inducing P-gp expression in NS.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Biomarkers; Child; Female; Flow Cytometry; Genotyping Techniques; Humans; Leukocytes, Mononuclear; Male; Multidrug Resistance-Associated Proteins; Nephrotic Syndrome
PubMed: 34011975
DOI: 10.1038/s41397-021-00233-9 -
International Journal of Molecular... Dec 2022The blood-brain barrier (BBB) controls brain homeostasis; it is formed by vascular endothelial cells that are physically connected by tight junctions (TJs). The BBB...
The blood-brain barrier (BBB) controls brain homeostasis; it is formed by vascular endothelial cells that are physically connected by tight junctions (TJs). The BBB expresses efflux transporters such as P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), which limit the passage of substrate molecules from blood circulation to the brain. Focused ultrasound (FUS) with microbubbles can create a local and reversible detachment of the TJs. However, very little is known about the effect of FUS on the expression of efflux transporters. We investigated the in vivo effects of moderate acoustic pressures on both P-gp and BCRP expression for up to two weeks after sonication. Magnetic resonance-guided FUS was applied in the striatum of 12 rats. P-gp and BCRP expression were determined by immunohistochemistry at 1, 3, 7, and 14 days postFUS. Our results indicate that FUS-induced BBB opening is capable of (i) decreasing P-gp expression up to 3 days after sonication in both the treated and in the contralateral brain regions and is capable of (ii) overexpressing BCRP up to 7 days after FUS in the sonicated regions only. Our findings may help improve FUS-aided drug delivery strategies by considering both the mechanical effect on the TJs and the regulation of P-gp and BCRP.
Topics: Rats; Animals; Blood-Brain Barrier; ATP Binding Cassette Transporter, Subfamily G, Member 2; Pilot Projects; ATP Binding Cassette Transporter, Subfamily B, Member 1; Endothelial Cells; Neoplasm Proteins; Neoplasms; Brain; ATP Binding Cassette Transporter, Subfamily B; Microbubbles
PubMed: 36555129
DOI: 10.3390/ijms232415488 -
Fundamental & Clinical Pharmacology Aug 2023The objective of this study was to investigate the effect of clarithromycin on the pharmacokinetics of tacrolimus in rats and better understand its mechanism. In the...
The objective of this study was to investigate the effect of clarithromycin on the pharmacokinetics of tacrolimus in rats and better understand its mechanism. In the control group (n = 6), rats received a single oral dose of 1 mg tacrolimus on day 6. In the experimental group (n = 6), rats received 0.25 g of clarithromycin daily for five consecutive days and then a single oral dose of 1 mg tacrolimus on day 6. Orbital venous blood (250 μL) was collected at 0, 0.25, 0.50, 0.75, 1, 2, 4, 8, 12, and 24 h before and after tacrolimus administration. Blood drug concentrations were detected via mass spectrometry. Small intestine and liver tissue samples were collected after rats were euthanized via dislocation, and CYP3A4 and P-glycoprotein (P-gp) protein expression was determined using western blotting. Clarithromycin increased the blood tacrolimus concentration and affected its pharmacokinetic properties in rats. Compared with those in the control group, the AUC , AUC , AUMC , and AUMC of tacrolimus in the experimental group were significantly increased, whereas the CLz/F was significantly lower (P < 0.01). Simultaneously, clarithromycin significantly inhibited CYP3A4 and P-gp expression in the liver and intestine. Protein expression of CYP3A4 and P-gp in the liver and the intestinal tract was significantly downregulated in the intervention group compared with that in the control group. Clarithromycin significantly inhibited the protein expression of CYP3A4 and P-gp in the liver and intestine, thereby increasing the mean blood concentration and significantly increasing the AUC of tacrolimus.
Topics: Animals; Rats; ATP Binding Cassette Transporter, Subfamily B, Member 1; Clarithromycin; Cytochrome P-450 CYP3A; Tacrolimus
PubMed: 36811298
DOI: 10.1111/fcp.12882 -
Biochemical and Biophysical Research... Jun 2022Multidrug resistant tumor cells show collaterally sensitive to a range of non-toxic drugs. In this report, we describe the isolation of several P-glycoprotein-knockout...
Multidrug resistant tumor cells show collaterally sensitive to a range of non-toxic drugs. In this report, we describe the isolation of several P-glycoprotein-knockout cell clones, using CRISPR/Cas9, from Chinese hamster multidrug resistant model cell line and its parental cells (e.g., CHOC5 and AuxB1, respectively). All three P-glycoprotein-knockout clones of CHOC5 cells show complete loss of resistance to anti-cancer drugs (e.g., colchicine and doxorubicin), while gaining resistance to well characterized collateral sensitivity drugs (e.g., verapamil, progesterone and NSC73306). A correlation between P-glycoprotein and Sorcin expression levels and a possible role for the latter in low grade resistance to colchicine and doxorubicin was observed. Furthermore, we show that P-glycoprotein expression is necessary for the ROS-mediated mechanism of collateral sensitivity. However, expectantly, P-glycoprotein-knockout clones of CHOC5 cells revealed a dramatic increase in the accumulation of Rhodamine 123, Mito tracker red and doxorubicin, but not Hoechst 33342. The latter findings and their significance to P-glycoprotein collateral sensitivity remain to be determined.
Topics: ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Animals; CHO Cells; Colchicine; Cricetinae; Doxorubicin; Drug Collateral Sensitivity; Drug Resistance; Verapamil
PubMed: 35381425
DOI: 10.1016/j.bbrc.2022.03.148 -
Toxicology in Vitro : An International... Apr 2023The methylimidazolium ionic liquid M8OI was recently found to be present in both the environment and man. In this study, M8OI disposition and toxicity were examined in...
The methylimidazolium ionic liquid M8OI was recently found to be present in both the environment and man. In this study, M8OI disposition and toxicity were examined in an established rat progenitor-hepatocyte model. The progenitor B-13 cell was approx. 13 fold more sensitive to the toxic effects of M8OI than the hepatocyte B-13/H cell. However, this difference in sensitivity was not associated with a difference in metabolic capacities. M8OI toxicity was significantly decreased in a dose-dependent manner by co-addition of the OCT1 (SLC22A1) inhibitor clonidine, but not by OCT2 or OCT3 inhibitors in B-13 cells. M8OI toxicity was also dose-dependently increased by the co-addition of p-glycoprotein-1 (ABCB1B, multi drug resistant protein 1 (MDR1)) substrates/inhibitors. Excretion of B-13-loaded fluorophore Hoechst 33342 was also inhibited by the p-glycoproteins substrate cyclosporin A and by M8OI in a dose-dependent manner. Comparing levels of OCT and p-glycoprotein transcripts and proteins in B-13 and B-13/H cells suggest that the lower sensitivity to M8OI in B-13/H cells is predominantly associated with their higher expression of p-glycoprotein-1. These data together therefore suggest that a determinant in M8OI toxicity in rats is the expression and activity of the p-glycoprotein-1 transporter.
Topics: Animals; Rats; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Hepatocytes; Imidazoles; Catecholamine Plasma Membrane Transport Proteins
PubMed: 36603777
DOI: 10.1016/j.tiv.2022.105550