OBJECTIVETo study the transport mechanism of baicalin of Scutellariae Radix extracts and the effect of Angelica dahurica extracts on the intestinal absorption of baicalin by using Caco-2 cell monolayer model, in order to analyze the effect mechanism of Angelica dahurica extracts on the intestinal absorption of baicalin.

METHODThe Caco-2 cell monolayer model was established with human colonic adenocarcinoma cells, and used to study the effect of pH, time, drug concentration and temperature on the transport of baicalin in Scutellariae Radix extracts, the effect of P-gp and MRP protein-dedicated inhibitors on the bidirectional transport of baicalin in Caco-2 cell model, and the effect of angelica root extracts on baicalin absorption and transport.

RESULTBaicalin was absorbed well at 37 degrees C and under pH 7.4 condition and concentration dependent. Its proteins became inactive at 4 degrees C, with a low transport. The bi-drectional transfer PDR was 0. 54. After P-gp inhibitor verapamil and MRP inhibitor probenecid were added, the value of PappBL-AP of baicalin decreased, but without any difference in PDR. The transport of baicalin was improved by 2.34, 3.31 and 3.13 times, after A. dahurica extract coumarin, volatile oil, and mixture of coumarin and volatile oil.

CONCLUSIONThe transport mechanism of baicalin is mainly passive transfer and supplemented with efflux proteins involved. A. dahurica extracts can enhance the absorption of baicalin, which may be related to the passive transfer merchanism of baicalin. A. dahurica extracts' effect in opening the close junction among cells may be related to its expression or function in inhibiting efflux proteins.

ATP-Binding Cassette, Sub-Family B, Member 1 ; antagonists & inhibitors ; metabolism ; Angelica ; chemistry ; Biological Transport ; drug effects ; Caco-2 Cells ; Cell Line, Tumor ; Coumarins ; chemistry ; pharmacology ; Drug Interactions ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Flavonoids ; pharmacokinetics ; Humans ; Intestinal Absorption ; drug effects ; physiology ; Oils, Volatile ; chemistry ; pharmacology ; Plant Extracts ; chemistry ; pharmacology ; Plant Roots ; chemistry ; Probenecid ; pharmacology ; Scutellaria baicalensis ; chemistry ; Verapamil ; pharmacology

Limonin existed in citrus fruits has been shown to have anti-bacterial, anti-viral, anti-feedant, anti-nociceptive, anti-inflammatory activities and anti-carcinogenic activities. But the clinical use is limited by its low bioavailability. The aim of this study is to observe the absorption and secretion transport mechanisms of limonin in intestine which can pave the way for the further study and clinical use. The transport characteristics and mechanisms of limonin in rat were studied by in situ intestine perfusion and in vitro Caco-2 cells method. The intestinal absorption of limonin was probably via a facilitated diffusion pathway which was poor and without segment-selection. Verapamil and ketoconazole improved the absorption remarkably according to the result of in vitro Caco-2 cells study; however, probenecid had no significant effect on the absorption. The P-gp efflux and CYP3A4 metabolism were involved in the poor intestinal absorption and low bioavailability of limonin. The exploration of the intestinal absorption mechanism is crucial to the design of dosage form and clinical use of limonin.
ATP-Binding Cassette, Sub-Family B, Member 1 ; metabolism ; Animals ; Biological Availability ; Biological Transport ; drug effects ; Caco-2 Cells ; Cytochrome P-450 CYP3A ; metabolism ; Dose-Response Relationship, Drug ; Humans ; Intestinal Absorption ; drug effects ; Ketoconazole ; pharmacology ; Limonins ; administration & dosage ; pharmacokinetics ; Male ; Perfusion ; Probenecid ; pharmacology ; Rats ; Verapamil ; pharmacology

Gout is an inflammatory arthritis characterized by recurrent attacks of inflammation caused by precipitation of monosodium urate crystals (MSU) in the joint and is associated with impaired quality of life. The incidence and prevalence of gout is increasing world wide due to the increasing size of the elderly population, kidney disease, diuretic use, dietary changes, and obesity. Furthermore, emerging evidence suggests that gout is strongly associated with metabolic syndrome and may lead to myocardial infarction, type 2 diabetes mellitus, and premature death. Urate nephropathy is also increasing. Thus, the overall disease and the economic burden of gout is substantial and increasing sharply. Although traditional urate lowering agents including allopurinol, probenecid, and benzbromarone have been available for many years, questions still remain about the optimal dosing regimen. Many patients remain undertreated for this potentially curable disorder. Fortunately, more scientific data and evidence for proper management of gout are available. Renewed interest in gout has led to advances in dietary advice and development of new therapeutic options. The importance of risk factors for gout should be emphasized and patients with gout and hyperuricemia should be educated so that they can achieve a good quality of life and longevity. In this review, the comorbidity, mortality, and economic burdens of gout will be presented. In addition, the importance of proper management and patient education will be stressed.
Aged ; Allopurinol ; Arthritis ; Benzbromarone ; Comorbidity ; Diabetes Mellitus, Type 2 ; Gout ; Humans ; Hyperuricemia ; Incidence ; Inflammation ; Joints ; Kidney Diseases ; Longevity ; Mortality, Premature ; Myocardial Infarction ; Obesity ; Patient Education as Topic ; Prevalence ; Probenecid ; Quality of Life ; Risk Factors ; Uric Acid

OBJECTIVETo explore a more effective therapy for acute gouty arthritis.

METHODSSixty cases were randomly divided into an observation group and a control group, 30 cases in eachgroup. On the basis of diet intervention, the observation group was treated with electroacupuncture at local points combined with blood-letting puncture and cupping, and the control group with oral administration of Probenecid. Their therapeutic effects were ob served.

RESULTSThe effective rate was 96.7% in the observation group which was better than 86.7% in the control group (P < 0.01). After treatment, blood uric acid decreased significantly in the two groups (both P < 0.01), the observed group being lower than the control group (P < 0.01).

CONCLUSIONOn the basis of diet intervention, electroacupuncture plus blood-letting puncture and cupping is a better therapy for acute gouty arthritis.

Adult ; Aged ; Arthritis, Gouty ; diet therapy ; drug therapy ; therapy ; Bloodletting ; Combined Modality Therapy ; Electroacupuncture ; Humans ; Male ; Middle Aged ; Probenecid ; therapeutic use ; Uricosuric Agents ; therapeutic use

PURPOSE: Systemic inflammatory reaction (SIR) is an important determinant of cardiovascular (CV) mortality in CRF patients. UA is an end-product of purine metabolism, and recent studies have demonstrated that an elevated serum UA level is associated with an increased level of inflammatory mediators. Since hyperuricemia is one of the most prevalent complications in CRF and is linked to CV disease, we hypothesized hyperuricemia in CRF may play an important role in the development of CV disease by inducing SIR. METHODS: PBMCs were isolated by density gradient centrifugation in 21 CRF patients and age and sex-matched 20 healthy adults. CRP expression was evaluated by real time PCR and ELISA in PBMC stimulated with UA (0.3-12 mg/dL). RESULTS: There was no difference in constitutional CRP expression in PBMC from control and CRF patients. UA induced CRP mRNA (RT-PCR) and protein (ELISA) expression in PBMC, which was blocked by the organic anion transport inhibitor, probenecid (1 mM), suggesting entry of uric acid into cells was responsible for CRP expression. PBMC from CRF patients showed a significantly higher CRP production by UA compared to healthy control. There was no correlation between serum UA level and % increase in CRP production by UA. CONCLUSION: The exaggerated CRP expression by UA can be another mechanism of SIR and increased CV morbidity in CRF patients. Prospective studies with uric acid-lowering therapy are necessary to confirm clinical significance of these interesting in-vitro findings.
Adult ; C-Reactive Protein* ; Cardiovascular Diseases ; Centrifugation, Density Gradient ; Enzyme-Linked Immunosorbent Assay ; Humans ; Hyperuricemia ; Inflammation ; Metabolism ; Mortality ; Probenecid ; Real-Time Polymerase Chain Reaction ; RNA, Messenger ; Uric Acid*

The first clinical infections with polyomavirus (PV) were demonstrated in 1971, when BK virus was isolated from the urine after a kidney transplant recipient and JC virus from the brain of a patient who died of progressive multifocal leukoencephalopathy. Polyomavirus-associated nephropathy (PVAN) has become an important cause of allograft dysfunction and loss in kidney transplantation since first recognized in kidney transplant recipient with PVAN in 1995. Most cases of PVAN are caused by polyomavirus hominis type 1, known as BK virus and arise while the patient in on triple immunosuppressive combinations, often comprising tacrolimus and/or mycophenolate mofetil plus corticosteroids. Significant progress has been made, particularly in the area of diagnostic methods for PV, facilitating diagnosis, screening and monitoring of PV infection. Definitive diagnosis of PVAN requires allograft kidney biopsy. Immunologic control of PV replication can be achieved by reducing, switching, and discontinuing of the immunusuppressive agents. Cidofovir and leflunomide are used empirically in the treatment of PVAN. However, these antiviral agents are not approved for PVAN. Recently, investigational use at low-dose cidofovir (0.25~0.33 mg/kg intravenously biweekly) without probenecid should be considered for the treatment of cases refractory to decreasedmaintenance immunosuppression. PVAN had a serious consequence of kidney transplantation that increasingly cause for chronic allograft kidney loss. Despite reduction in immuo-suppression, allograft kidney loss occurred in 46% of transplant recipients with PVAN. PVAN recurred in 15% of retransplantations compared with 5% of primary kidney transplantations. However, retransplantation is not contraindicated for transplant recipient in whom a first allograft kidney lost due to PVAN. Recently, preemptive retransplantation can be considered in patients with allograft loss due to PVAN.
Adrenal Cortex Hormones ; Allografts ; Antiviral Agents ; Biopsy ; BK Virus ; Brain ; Diagnosis ; Humans ; Immunosuppression ; JC Virus ; Kidney ; Kidney Transplantation* ; Leukoencephalopathy, Progressive Multifocal ; Mass Screening ; Polyomavirus ; Probenecid ; Tacrolimus ; Transplantation

PURPOSE: Multidrug resistance (MDR) is a phenomenon whereby tumor cells acquire resistance to a broad range of structurally and functionally diverse chemotherapeutic drugs. The most widely implicated mechanism of MDR is that concerned with altered membrane transporters in tumor cells. P-glycoprotein (Pgp), multidrug resistance protein (MRP), and breast-cancer-resistance protein (BCRP) are well-known membrane transporters that pump out antitumor agents by using an ATP-dependent process, the so-called ATP-binding cassette (ABC) superfamily or transporter. This study was undertaken to test the prevalence of each ABC transporter and to determine which transporter has functional acitivity in various colon cancer cells. METHODS: Expressions of Pgp, MRP, and BCRP mRNA were determined in 9 colon-cancer cell lines by using an RT-PCR assay. The sensitivity to anticancer agents substrate for each ABC transporter in the colon cancer cells determined using an MTT assay. The accumulation of fluorescent compounds for functional detection of each ABC transporter was determined by using flow cytometry. RESULTS: Pgp mRNA was variably expressed in 6 of 9 colon cancer cells lines. MRP and BCRP mRNA were expressed in all the 9 cell lines. A smaller cytotoxic effect to paclitaxel and a smaller amount of rhodamine123 accumulation were observed in Colo 320HSR expressing the highest levels of Pgp than in SNU-C5 not expressing Pgp. These effects in Colo320HSR were reversed with the addition of various Pgp inhibitors, but such a reversal did not occur in SNU-C5. The cytotoxic effect to VP-16 was not related to the expression levels of MRP in Colo320HSR and SNU-C, but the amount of calcein-AM accumulation was reversed with addition of probenecid, MRP inhibitor. The cytotoxic effect and the drug accumulation of mitoxantrone were not related to the expression levels of BCRP. CONCLUSIONS: This study suggests that of the ABC transporters, primarily Pgp and MRP have functional activity in colon cancer cell lines.
Antineoplastic Agents ; ATP-Binding Cassette Transporters* ; Cell Line ; Colon* ; Colonic Neoplasms* ; Drug Resistance, Multiple* ; Etoposide ; Flow Cytometry ; Membrane Transport Proteins ; Mitoxantrone ; P-Glycoprotein ; Paclitaxel ; Prevalence ; Probenecid ; RNA, Messenger

PURPOSE: Multidrug resistance (MDR) is a phenomenon whereby tumor cell acquire resistance to a broad range of structurally and functionally diverse chemotherapeutic drugs. The most widely implicated mechanism of MDR is that of altered membrane transporter in tumor cells. P-glycoprotein (Pgp), multidrug resistance protein (MRP), and breast cancer-resistance protein (BCRP) are well known membrane transporters, which pump out antitumor agents via an ATP-dependent process, the so called ATP-binding cassette (ABC) superfamily or transporter. This study was undertaken to test the prevalence of each ABC transporter, and which of then exhibit functional activity in various gastric cancer cells. METHODS: The expressions of Pgp, MRP, and BCRP mRNA were determined by RT-PCR assay on 10 gastric cancer cells. The sensitivity to anticancer agents, substrates for each ABC transporter in the gastric cancer cells was determined using the MTT assay. The intracellular accumulation of fluorescent compounds for the functional detection of each ABC transporter was determined using flow cytometry. RESULTS: The Pgp mRNA was expressed at various levels in 9 out of the 10 gastric cancer cells tested, but significantly low. MRP mRNA was constitutively expressed in all the cells. BCRP mRNA was differentially expressed in 5 of the gastric cancer cells. There was no relation between the expressions of Pgp and MRP and the cytotoxicity to each substrate. It was observed that the accumulations of paclitaxel and VP-16 were significantly increased on the additions of PSC833 and probenecid, respectively, in all tested cells. The reversal effect of drug accumulation by each inhibitor was much higher in the MRP than Pgp. With BCRP, the observed cytotoxic effect and amount of mitoxanthrone accumulation were less than in the cells expressing the highest levels of BCRP compared to those that did not. However the mitoxanthrone accumulation was not increased on the addition of FTC in the either cell type. CONCLUSION: This study suggests that of the ABC transporters, MRP has primarily functional activity, whereas that of Pgp is only slight, in the gastric cancer cells. Other possible MDR mechanisms involved will have to be explored in further studies.
Antineoplastic Agents ; ATP-Binding Cassette Transporters* ; Breast ; Drug Resistance, Multiple* ; Etoposide ; Flow Cytometry ; Membrane Transport Proteins ; Membranes ; P-Glycoprotein ; Paclitaxel ; Prevalence ; Probenecid ; RNA, Messenger ; Stomach Neoplasms*

Glycogen storage diseases(GSD) are inherited disorders affecting glycogen metabolism and type I GSD is due to the absence or deficiency of glucose-6-phosphatase(G6Pase) enzyme in the liver, kidney, and intestinal mucosa. The defect leads to inadequate hepatic conversion of G6P to glucose and thus make affected individuals susceptible to fasting hypoglycemia, and the accumulation of glycogen occurs in the liver and other organs. Type Ia is the most common form of GSD and clinically growth retardation may manifest of GSD itself rather than growth hormone deficiency(GHD), but we experienced a case of type I GSD with GHD in a 14-year-o1d male. The height was 125 cm, compatible with 50 th percentile of height of 8 years of age. He has doll-like face with fat cheek, relatively thin extremities, and metabolic acidosis, hyperuricemia, hypoglycemia, hyperlipidemia. GH stimulation test with clonidine and L-dopa revealed that the patient had decreased GH secretion. After laboratory work up including liver biopsy, he was diagnosed as type I GSD. Hypoglycemia was managed with frequent feeding with high starch diet(uncooked cornstarch). Metabolic acidosis and hyperuricemia were treated with sodium bicarbonate, allopurinol and probenecid. The patient is being followed at out-patient clinic with clinical improvement after of diet therapy and GH administration.
Acidosis ; Allopurinol ; Biopsy ; Cheek ; Clonidine ; Diet Therapy ; Extremities ; Glucose ; Glycogen Storage Disease* ; Glycogen* ; Growth Hormone* ; Humans ; Hyperlipidemias ; Hyperuricemia ; Hypoglycemia ; Intestinal Mucosa ; Kidney ; Levodopa ; Liver ; Male ; Metabolism ; Outpatients ; Probenecid ; Sodium Bicarbonate ; Starch

We encountered a case of renal hypouricemia and absorptive hypercalciuria. Although renal hypouricemia is asymptomatic as usual, it is rarely complicated with acute renal failure and urolithiasis. A 43-year-old man had hypouricemia (serum uric acid, 0.6-1.0mg/dl) with an increased renal uric acid clearance (69.4ml/min), hypercalciuria (367.2mg/day). In present case, there was no response of uric acid excretion to either pyrazinamide or probenecid and hypercalciuria disappeared after calcium restriction diet. These results suggest that the present case had the defect of both pre-and postsecretory reabsorption of uric acid and absorptive hypercalciuria.
Acute Kidney Injury ; Adult ; Calcium ; Diet ; Humans ; Hypercalciuria* ; Probenecid ; Pyrazinamide ; Uric Acid ; Urolithiasis