OBJECTIVESThe aim of this study is to evaluate the hepatoprotective effect of Lasianthera africana (Icacinaceae) against isoniazid (INH) and rifampicin (RIF)-induced liver damage in rats.

METHODSThe hepatoprotective effects of hot aqueous L. africana (HALA) leaf extract (0.1-1 g/kg) and silymarin (50 mg/kg) were assessed in a model of oxidative liver damage induced by RIF and INH (100 mg/kg each) in Wistar rats for 28 days. Biochemical markers of hepatic damage such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were assessed. The antioxidant statuses of plasma glutathione peroxidase (GSPx), glutathione reductase (GSH), catalase (CAT) and superoxide dismutase (SOD) and lipid peroxidation were evaluated.

RESULTSThe pretreatment of INH and RIF decreased hematological indices and the antioxidant levels (P < 0.001) and increased the levels of liver marker enzymes (P < 0.001). However, pretreatment with HALA extract and silymarin provoked significant elevation of hematological indices. The levels of AST, ALT, and ALP were depressed (P < 0.001). Total triglycerides, total cholesterol, total bilirubin and low-density lipoprotein were decreased (P < 0.001). However, high-density lipoprotein, bicarbonate, and electrolytes like chloride and potassium were elevated (P < 0.001), but sodium was depressed (P < 0.05). Additionally, GSH, GSPx, SOD and CAT were elevated (P < 0.01) and malondialdehyde was depressed (P < 0.001) when compared to the RIF-INH-treated rats. Histopathological evaluations support hepatoprotective activity.

CONCLUSIONThis study demonstrated that HALA leaf extract attenuated RIF-INH-induced hepatotoxicity. L. africana could be exploited in management of RIF-INH-induced hepatitis.

Alanine Transaminase ; metabolism ; Animals ; Antibiotics, Antitubercular ; toxicity ; Aspartate Aminotransferases ; metabolism ; Chemical and Drug Induced Liver Injury ; drug therapy ; etiology ; metabolism ; Cholesterol ; metabolism ; Female ; Glutathione ; metabolism ; Humans ; Isoniazid ; toxicity ; Liver ; drug effects ; enzymology ; Magnoliopsida ; chemistry ; Male ; Malondialdehyde ; metabolism ; Plant Extracts ; administration & dosage ; Plant Leaves ; chemistry ; Rats, Wistar ; Rifampin ; toxicity ; Superoxide Dismutase ; metabolism

Atopic dermatitis (AD) is a common inflammatory skin disorder mediated by inflammatory cells, such as macrophages and mast cells. Rifampicin is mainly used for the treatment of tuberculosis. Recently, it was reported that rifampicin has anti-inflammatory and immune-suppressive activities. In this study, we investigated the effect of rifampicin on atopic dermatitis in vivo and in vitro. AD was induced by treatment with 2, 4-dinitrochlorobenzene (DNCB) in NC/Nga mice. A subset of mice was then treated with rifampicin by oral administration. The severity score and scratching behavior were alleviated in the rifampicin-treated group. Serum immunoglobulin E (IgE) and interleukin-4 (IL-4) levels were also ameliorated in mice treated with rifampicin. We next examined whether rifampicin has anti-atopic activity via suppression of mast cell activation. Rifampicin suppressed the release of β-hexosaminidase and histamine from human mast cell (HMC)-1 cultures stimulated with compound 48/80. Treatment with rifampicin also inhibited secretion of inflammatory mediators, such tumor necrosis factor-α (TNF-α) and prostaglandin D₂ (PGD₂), in mast cells activated by compound 48/80. The mRNA expression of cyclooxygenase 2 (COX-2) was reduced in the cells treated with rifampicin in a concentration-dependent manner. These results suggest that rifampicin can be used to treat atopic dermatitis.
Administration, Oral ; Animals ; Cyclooxygenase 2 ; Dermatitis, Atopic ; Histamine ; Humans ; Immunoglobulin E ; Immunoglobulins ; In Vitro Techniques* ; Interleukin-4 ; Macrophages ; Mast Cells ; Mice ; Necrosis ; Rifampin* ; RNA, Messenger ; Skin ; Tuberculosis

Atopic dermatitis (AD) is a common inflammatory skin disorder mediated by inflammatory cells, such as macrophages and mast cells. Rifampicin is mainly used for the treatment of tuberculosis. Recently, it was reported that rifampicin has anti-inflammatory and immune-suppressive activities. In this study, we investigated the effect of rifampicin on atopic dermatitis in vivo and in vitro. AD was induced by treatment with 2, 4-dinitrochlorobenzene (DNCB) in NC/Nga mice. A subset of mice was then treated with rifampicin by oral administration. The severity score and scratching behavior were alleviated in the rifampicin-treated group. Serum immunoglobulin E (IgE) and interleukin-4 (IL-4) levels were also ameliorated in mice treated with rifampicin. We next examined whether rifampicin has anti-atopic activity via suppression of mast cell activation. Rifampicin suppressed the release of β-hexosaminidase and histamine from human mast cell (HMC)-1 cultures stimulated with compound 48/80. Treatment with rifampicin also inhibited secretion of inflammatory mediators, such tumor necrosis factor-α (TNF-α) and prostaglandin D₂ (PGD₂), in mast cells activated by compound 48/80. The mRNA expression of cyclooxygenase 2 (COX-2) was reduced in the cells treated with rifampicin in a concentration-dependent manner. These results suggest that rifampicin can be used to treat atopic dermatitis.
Administration, Oral ; Animals ; Cyclooxygenase 2 ; Dermatitis, Atopic ; Histamine ; Humans ; Immunoglobulin E ; Immunoglobulins ; In Vitro Techniques* ; Interleukin-4 ; Macrophages ; Mast Cells ; Mice ; Necrosis ; Rifampin* ; RNA, Messenger ; Skin ; Tuberculosis

OBJECTIVETo fabricate a new composite scaffold material as an implant for sustained delivery of rifampicin and evaluate its performance of sustained drug release and biocompatibility.

METHODSThe composite scaffold material was prepared by loading poly(lactic-co-glycolic) acid (PLGA) microspheres that encapsulated rifampicin in a biphasic calcium composite material with a negative surface charge. The in vitro drug release characteristics of the microspheres and the composite scaffold material were evaluated; the in vivo drug release profile of the composite scaffold material implanted in a rat muscle pouch was evaluated using high-performance liquid chromatography. The biochemical parameters of the serum and liver histopathologies of the rats receiving the transplantation were observed to assess the biocompatibility of the composite scaffold material.

RESULTSThe encapsulation efficiency and drug loading efficiency of microspheres were (56.05±5.33)% and (29.80±2.88)%, respectively. The cumulative drug release rate of the microspheres in vitro was (94.19±5.4)% at 28 days, as compared with the rate of (82.23±6.28)% of composite scaffold material. The drug-loaded composite scaffold material showed a good performance of in vivo drug release in rats, and the local drug concentration still reached 16.18±0.35 µg/g at 28 days after implantation. Implantation of the composite scaffold material resulted in transient and reversible liver injury, which was fully reparred at 28 days after the implantation.

CONCLUSIONThe composite scaffold material possesses a good sustained drug release capacity and a good biocompatibility, and can serve as an alternative approach to conventional antituberculous chemotherapy.

Animals ; Biocompatible Materials ; chemistry ; Delayed-Action Preparations ; Drug Carriers ; chemistry ; Drug Liberation ; Lactic Acid ; chemistry ; Microspheres ; Polyglycolic Acid ; chemistry ; Rats ; Rifampin ; administration & dosage

OBJECTIVE: To prepare the slow-release complex with rifampicin (RFP)-polylactic-co-glycolic acid (PLGA)-calcium phosphate cement (CPC) (RFP-PLGA-CPC complex), and to study its physical and chemical properties and drug release properties in vitro.
 METHODS: The emulsification-solvent evaporation method was adopted to prepare rifampicin polylactic acid-glycolic acid (RFP-PLGA) slow-release microspheres, which were divided into 3 groups: a calcium phosphate bone cement group (CPC group), a CPC embedded with RFP group (RFP-CPC group), and a PLGA slow-release microspheres carrying RFP and the self-curing CPC group (RFP- PLGA-CPC complex group). The solidification time and porosity of materials were determined. The drug release experiments in vitro were carried out to observe the compressive strength, the change of section morphology before and after drug release. 
 RESULTS: The CPC group showed the shortest solidification time, while the RFP-PLGA-CPC complex group had the longest one. There was statistical difference in the porosity between the CPC group and the RFP-CPC group (P<0.05); Compared to the RFP-PLGA-CPC complex group, the porosity in the CPC group and the RFP-CPC group were significantly changed (both P<0.01). There was significant difference in the compressive strength between the RFP- PLGA-CPC complex group and the CPC group (P<0.01), while there was significant difference in the compressive strength between the RFP-CPC group and the CPC group (3 days: P<0.05; 30 and 60 days: P<0.01). The change of the compressive strength in the CPC was not significant in the whole process of degradation. The sizes of PLGA microspheres were uniform, with the particle size between 100-150 μm. The microspheres were spheres or spheroids, and their surface was smooth without the attached impurities. There was no significant change in the section gap in the CPC group after soaking for 3 to 60 days. The microstructure change in the RFP-CPC group was small, and the cross section was formed by small particles. The pores of section in the RFP-PLGA-CPC complex group increased obviously, and PLGA microspheres gradually disappeared until the 60th day when there were only empty cavities left. The RFP-PLGA-CPC complex group had no obvious drugs sudden release, and the cumulative drug release rate was nearly 95% in the 60 days. The linear fitting was conducted for the drug release behavior of the complex, which was in accordance with zero order kinetics equation F=0.168×t.
 CONCLUSION The porosity of RFP-PLGA-CPC complex is significantly higher than that of CPC, and it can keep slow release of the effective anti-tuberculosis drugs and maintain a certain mechanical strength for a long time.
Bone Cements ; pharmacokinetics ; Calcium Phosphates ; pharmacokinetics ; Compressive Strength ; Delayed-Action Preparations ; pharmacokinetics ; Dental Cements ; pharmacokinetics ; Lactic Acid ; pharmacokinetics ; Materials Testing ; Microspheres ; Polyglycolic Acid ; pharmacokinetics ; Polylactic Acid-Polyglycolic Acid Copolymer ; Porosity ; Rifampin ; administration & dosage ; pharmacokinetics

BACKGROUNDDecreases in the bioavailability of rifampicin (RFP) can lead to the development of drug resistance and treatment failure. Therefore, we investigated the relative bioavailability of RFP from one four-drug fixed-dose combination (FDC; formulation A) and three two-drug FDCs (formulations B, C, and D) used in China, compared with RFP in free combinations of these drugs (reference), in healthy volunteers.

METHODSEighteen and twenty healthy Chinese male volunteers participated in two open-label, randomized two-period crossover (formulations A and C) or one three-period crossover (formulations B and D) study, respectively. The washout period between treatments was 7 days. Bioequivalence was assessed based on 90% confidence intervals, according to two one-sided t-tests. All analyses were done with DAS 3.1.5 (Mathematical Pharmacology Professional Committee of China, Shanghai, China).

RESULTSMean pharmacokinetic parameter values of RFP obtained for formulations A, B, C, and D products were 11.42 ± 3.41 μg/ml, 7.86 ± 5.78 μg/ml, 13.05 ± 6.80 μg/ml, and 16.18 ± 3.87 μg/ml, respectively, for peak plasma concentration (C max ), 91.43 ± 30.82 μg·h-1·ml-1 , 55.49 ± 37.58 μg·h-1·ml-1 , 96.50 ± 47.24 μg·h-1·ml-1 , 101.47 ± 33.07 μg·h-1·ml-1 , respectively, for area under the concentration-time curve (AUC 0-24 h ).

CONCLUSIONSAlthough the concentrations of RFP for formulations A, C, and D were within the reported acceptable therapeutic range, only formulation A was bioequivalent to the reference product. The three two-drug FDCs (formulations B, C and D) displayed inferior RFP bioavailability compared with the reference (Chinese Clinical Trials registration number: ChiCTR-TTRCC-12002451).

Adult ; Asian Continental Ancestry Group ; Biological Availability ; Drug Combinations ; Humans ; Male ; Rifampin ; administration & dosage ; pharmacokinetics ; therapeutic use ; Tuberculosis ; drug therapy ; Young Adult

Rifampin is commonly used as a first-line anti-tuberculosis drug, but it can induce a serum sickness-like reaction or anaphylaxis. However, it is possible for 1 drug antigen to induce 2 or more simultaneous immunologic reactions. Here, we report a case of a serum-sickness-like reaction and anaphylaxis induced concurrently by rifampin. A 25-year-old male presented with high fever and a maculopapular rash with vesicles on the hands, which developed 2 weeks following regular administration of anti-tuberculosis drugs for tuberculous meningitis, including rifampin. Elevated liver enzymes, peripheral neuropathy, and decreased serum C3 and C4 levels were found. Interestingly, these symptoms were accompanied by severe hypotension. A serum-sickness-like reaction was considered after excluding other potential causes for the fever. A drug provocation test showed that the fever developed after oral administration of rifampin, suggesting that rifampin was the cause of the allergic reaction. However, hypotension, epigastric discomfort, and diarrhea also accompanied these symptoms, indicating that IgE-mediated type I hypersensitivity could be part of the serum sickness-like reaction. An intradermal skin test clearly showed an immediate positive reaction to rifampin. This case was diagnosed as concurrent serum-sickness-like reaction and anaphylaxis induced by rifampin. One drug may therefore induce combined allergic reactions via 2 or more simultaneous hypersensitivity responses.
Administration, Oral ; Adult ; Anaphylaxis* ; Diarrhea ; Exanthema ; Fever ; Hand ; Humans ; Hypersensitivity ; Hypersensitivity, Immediate ; Hypotension ; Liver ; Male ; Peripheral Nervous System Diseases ; Rifampin* ; Skin Tests ; Tuberculosis, Meningeal

Anti-Inflammatory Agents ; administration & dosage ; Arthritis ; diagnosis ; drug therapy ; etiology ; physiopathology ; Arthritis, Rheumatoid ; diagnosis ; Clofazimine ; administration & dosage ; Dapsone ; administration & dosage ; Delayed Diagnosis ; Diagnosis, Differential ; Humans ; Leprostatic Agents ; administration & dosage ; Leprosy ; complications ; diagnosis ; drug therapy ; physiopathology ; Male ; Middle Aged ; Prednisolone ; administration & dosage ; Rifampin ; administration & dosage ; Treatment Outcome

Tuberculosis (TB) is prevalent and remains a major public health problem in South Korea. Joint committee for the development of Korean guidelines for TB has published a guideline for the treatment of TB recently. The aim of this guideline is to provide evidence based practical recommendations to clinicians caring TB patients in South Korea. Treatment regimen for the newly diagnosed TB is divided into 2 months of initial intensive phase (isoniazid, rifampin, ethambutol, pyrazinamide) followed by 4 months of maintenance phase (isoniazid, rifampin, ethambutol). Ethambutol may be dropped from the regimen after 2 months of treatment if bacilli is susceptible to isoniazid and rifampin (2HREZ/4HR). Because stopping medical treatment by the patient is most serious problem in the treatment of TB, this guideline emphasizes education and supervision of the patients to ensure patient's adherence to taking medicines.
Dietary Sucrose ; Ethambutol ; Humans ; Isoniazid ; Joints ; Organization and Administration ; Public Health ; Republic of Korea ; Rifampin ; Tuberculosis

The paper is aimed to study the metabolic characteristics of osthol (Ost) in isolated hepatocytes of rat to identify which isoforms of CYP450 were responsible for Ost metabolism in vitro. The concentration of Ost in isolated hepatocytes incubation system was determined by HPLC-UV. The effects of incubation time, substrate concentration and hepatocytes amount on the metabolic characteristics of Ost were investigated. CYP2C8 inhibitor quercetin (Que), CYP2C9 inhibitor sulfaphenazole (Sul), CYP2D6 inhibitor yohimbine (Yoh), CYP3A4 inhibitor troleandomycin (Tro) and CYP450 inducer rifampicin (Rif) were used to investigate their effects on the metabolism of Ost. The metabolism of Ost in isolated rat hepatocytes showed an enzymatic kinetic characteristics. Rif induced Ost elimination in rat hepatocytes; Yoh, Sul, Que did not have effects on Ost metabolism in vitro. Between 0-200 micromol x L(-1), Tro inhibited Ost metabolism in a concentration-dependent manner. CYP3A4 is the enzyme metabolizing Ost in vitro; CYP2C8, CYP2C9 and CYP2D6 did not involve in Ost metabolism in rat hepatocytes.
Animals ; Cells, Cultured ; Cnidium ; chemistry ; Coumarins ; isolation & purification ; metabolism ; Cytochrome P-450 CYP2D6 Inhibitors ; Cytochrome P-450 CYP3A ; Cytochrome P-450 Enzyme Inhibitors ; Cytochrome P-450 Enzyme System ; Hepatocytes ; metabolism ; Male ; Plants, Medicinal ; chemistry ; Quercetin ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Rifampin ; pharmacology ; Sulfaphenazole ; pharmacology ; Troleandomycin ; administration & dosage ; pharmacology ; Yohimbine ; pharmacology