Acetaminophen, also known as N-acetyl-p-aminophenol (APAP), is commonly used as an antipyretic and analgesic agent. APAP overdose can induce hepatic toxicity, known as acetaminophen-induced liver injury (AILI). However, therapeutic doses of APAP can also induce AILI in patients with excessive alcohol intake or who are fasting. Hence, there is a need to understand the potential pathological mechanisms underlying AILI. In this review, we summarize three main mechanisms involved in the pathogenesis of AILI: hepatocyte necrosis, sterile inflammation, and hepatocyte regeneration. The relevant factors are elucidated and discussed. For instance, N-acetyl-p-benzoquinone imine (NAPQI) protein adducts trigger mitochondrial oxidative/nitrosative stress during hepatocyte necrosis, danger-associated molecular patterns (DAMPs) are released to elicit sterile inflammation, and certain growth factors contribute to liver regeneration. Finally, we describe the current potential treatment options for AILI patients and promising novel strategies available to researchers and pharmacists. This review provides a clearer understanding of AILI-related mechanisms to guide drug screening and selection for the clinical treatment of AILI patients in the future.
Acetaminophen/toxicity* ; Analgesics, Non-Narcotic/toxicity* ; Animals ; Chemical and Drug Induced Liver Injury/pathology* ; Chemical and Drug Induced Liver Injury, Chronic/pathology* ; Humans ; Inflammation/metabolism* ; Liver/pathology* ; Mice ; Mice, Inbred C57BL ; Necrosis/pathology*

OBJECTIVETo explore the effect of lappaconitine on patient-controlled intravenous analgesia (PCIA) and serum complement 3 and 4 (C3 and C4) levels of cancer patients undergoing rectum surgery.

METHODSTotally 60 patients, who were scheduled for rectum carcinoma surgery, were recruited to the study and assigned in 3 groups, the blank control group, the tramadol group, and the lappaconitine group, 20 in each group. Lappaconitine (8 mg) was intravenously dripped to patients in the lappaconitine group 30 min before ending the operation. PCIA started as soon as the end of the surgery and the total dose of lappaconitine was 36 mg. Patients of the tramadol group were treated with tramadol (100 mg) intravenously within 30 min before ending the operation. The dripping was completed within 30 min. PCIA was started as soon as the end of the surgery and the total dose of lappaconitine was 36 mg. Tramadol (100 mg) was intravenously dripped to patients in the tramadol group 30 min before ending the operation. PICA was started as soon as the end of the surgery and the total dose of tramadol was 900 mg. Pethidine (50 mg) and droperidol (2. 5 mg) was intramuscularly injected to patients in the blank control group for pain relief according to their complaints. Pain degrees were assessed by visual analog scale (VAS) 12 h before surgery, 12, 24, 48, and 72 h after surgery. Blood samples were withdrawn at the same time point. Contents of serum C3 and C4 were determined by immunoturbidimetry.

RESULTSVAS scores of the blank control group were significantly higher after surgery than before surgery (P <0. 01). There was no statistical difference in VAS scores between before surgery and after surgery in the tramadol group and the lappaconitine group (P >0. 05). VAS scores were significantly lower at each post-surgery time point in the tramadol group and the lappaconitine group than in the blank control group with statistical difference (P < 0.01). There was no statistical difference in VAS scores at each post-surgery time point between the tramadol group and the lappaconitine group (P >0. 05). Compared with before surgery, contents of serum C3 and C4 significantly decreased in all of the three groups at 12, 24, and 48 h after surgery (P < 0.05, P < 0.01). They recovered to the pre-surgery level till 72 h after surgery (P > 0.05). Serum C3 and C4 contents at 48 h after surgery were higher in the tramadol group than in the blank control group (P < 0.05). Serum C3 and C4 contents at 24 and 48 h after surgery were higher in the lappaconitine group than in the blank control group (P < 0.05). There was no statistical difference in serum C3 and C4 contents at each time point between the tramadol group and the lappaconitine group (P > 0.05). VAS scores were obviously negatively correlated with serum contents of C3 and C4 (r = -0.622, r = -0.649, P < 0.01).

CONCLUSIONSLappaconitine (used at the dose in this study) showed better pain relief effect after surgery. Besides, it could inhibit the surgic wound and pain, and elevate serum contents of C3 and C4.

Aconitine ; analogs & derivatives ; therapeutic use ; Analgesia, Patient-Controlled ; methods ; Analgesics, Non-Narcotic ; therapeutic use ; Complement C3 ; metabolism ; Digestive System Surgical Procedures ; Humans ; Neoplasms ; Orthopedic Procedures ; Pain Measurement ; Pain, Postoperative ; Postoperative Period ; Rectum ; surgery ; Tramadol

To explore novel non-opioid analgesic agents, 16 compounds were synthesized and their structures were confirmed by 1H NMR and HR-MS. YX0611-1 was treated as the leading compound. The results of mice writhing model and hot plate model showed that compounds 2, 7, 8, 9, 11 and 15 had obvious analgesic activities in vivo. The test of affinity to mu, delta, kappa receptor displayed that active compounds didn't act on opioid receptor. The results of preliminary toxicity and pharmacokinetic tests showed that compound 7 had better safety and pharmacokinetic properties than that of YX0611-1, and it deserved further development.
Analgesics, Non-Narcotic ; chemical synthesis ; chemistry ; pharmacokinetics ; pharmacology ; toxicity ; Animals ; Female ; Male ; Mice ; Pain Measurement ; Piperazines ; chemical synthesis ; chemistry ; pharmacokinetics ; pharmacology ; toxicity ; Random Allocation ; Receptors, Opioid ; metabolism ; Structure-Activity Relationship

Rotundine (1 micromol L(-1)) was incubated with a panel of rCYP enzymes (1A2, 2C9, 2C19, 2D6 and 3A4) in vitro. The remained parent drug in incubates was quantitatively analyzed by an Agilent LC-MS. CYP2C19, 3A4 and 2D6 were identified to be the isoenzymes involved in the metabolism of rotundine. The individual contributions of CYP2C19, 3A4 and 2D6 to the rotundine metabolism were assessed using the method of total normalized rate to be 31.46%, 60.37% and 8.17%, respectively. The metabolites of rotundine in incubates were screened with ESI-MS at selected ion mode, and were further identified using MS2 spectra and precise molecular mass obtained from an Agilent LC/Q-TOF-MSMS, as well as MS(n) spectra of LC-iTrap-MS(n). The predominant metabolic pathway of rotundine in rCYP incubates was O-demethylation. A total 5 metabolites were identified including 4 isomerides of mono demethylated rotundine and one di-demethylated metabolite. The results also showed that CYP2C19, 2D6 and 3A4 mediated O-demethylation of methoxyl groups at different positions of rotundine. Furthermore, the ESI-MS cleavage patterns of rotundine and its metabolites were explored by using LC/Q-TOF-MSMS and LC/iTrap-MS(n) techniques.
Analgesics, Non-Narcotic ; metabolism ; Aryl Hydrocarbon Hydroxylases ; metabolism ; Berberine Alkaloids ; metabolism ; Chromatography, Liquid ; Cytochrome P-450 CYP1A2 ; metabolism ; Cytochrome P-450 CYP2C19 ; Cytochrome P-450 CYP2C9 ; Cytochrome P-450 CYP2D6 ; metabolism ; Cytochrome P-450 CYP3A ; metabolism ; Cytochrome P-450 Enzyme System ; metabolism ; Dopamine Antagonists ; metabolism ; Humans ; Isoenzymes ; metabolism ; Methylation ; Recombinant Proteins ; metabolism ; Spectrometry, Mass, Electrospray Ionization

A series of aralkyl-ketone-4-piperidol derivatives were synthesized and tested for their analgesic activities. All of the novel 30 compounds were prepared from 4-piperidone and alpha-halo-aralkyl-ketone through five steps, including Boc protection, nucleophilic addition in presence of CeCl3/NaI catalyst, deprotection, condensation and salification. Their structures were confirmed by 1H NMR and HRMS. Preliminary in vivo pharmacological trials showed that most of the synthesized compounds revealed analgesic effects. Among the tested compounds, 8, 13 and 22 exhibited potent analgesic activities in both mice writhing and mice hot plate model. The three compounds have low affinity for mu, delta, kappa receptors, which is a chance to find a better precursor of non-opioid analgesic for further optimization.
Analgesics, Non-Narcotic ; chemical synthesis ; chemistry ; pharmacology ; Animals ; Mice ; Molecular Structure ; Pain Measurement ; Pain Threshold ; drug effects ; Piperidones ; chemical synthesis ; chemistry ; pharmacology ; Receptors, Opioid, delta ; metabolism ; Receptors, Opioid, kappa ; metabolism ; Receptors, Opioid, mu ; metabolism ; Structure-Activity Relationship

OBJECTIVETo investigate the regulatory effects of nerve growth factor (NGF) on basal and capsaicin-induced release of neuropeptide substance P (SP) in primary cultured embryonic rat dorsal root ganglion (DRG) neurons.

METHODSDRGs were dissected from 15-day-old embryonic Wistar rats. DRG neurons were dissociated and cultured, and then exposed to different concentrations of NGF (10 ng/mL, 30 ng/mL, or 100 ng/mL) for 72 h. The neurons cultured in media without NGF served as control. RT-PCR were used for detecting the mRNAs of SP and vanilloid receptor 1 (VR1) in the DRG neurons. The SP basal and capsaicin (100 nmol/L)-induced release in the culture were measured by radioimmunoassay (RIA).

RESULTSSP mRNA and VR1 mRNA expression increased in primary cultured DRG neurons in a dose-dependent manner of NGF. Both basal release and capsaicin-evoked release of SP increased in NGF-treated DRG neurons compared with in control group. The capsaicin-evoked release of SP also increased in a dose-dependent manner of NGF.

CONCLUSIONNGF may promote both basal release and capsaicin-evoked release of SP. NGF might increase the sensitivity of nociceptors by increasing the SP mRNA or VR1 mRNA.

Analgesics, Non-Narcotic ; pharmacology ; Animals ; Capsaicin ; pharmacology ; Cells, Cultured ; Dose-Response Relationship, Drug ; Embryo, Mammalian ; Ganglia, Spinal ; cytology ; Gene Expression Regulation ; drug effects ; Nerve Growth Factor ; pharmacology ; Neurons ; drug effects ; RNA, Messenger ; metabolism ; Radioimmunoassay ; methods ; Rats ; Rats, Wistar ; Substance P ; genetics ; metabolism

The purpose of this study is to evaluate the interaction effects of In-Chen-How (Artemisia capillaries Thunb.) on the pharmacokinetics of acetaminophen and on liver microsomal cytochrome P450 enzyme activity in rats. The rats were divided into control group (n = 8) without In-Chen-How and the pretreated group (n = 8) administered with In-Chen-How (approximately 1.0 mL x kg(-1), according to weight) for 5 consecutive days. Rats in the control group received water simultaneously. Each rat was then given acetaminophen. The pharmacokinetic parameters of acetaminophen of the two groups were significantly different. In the In-Chen-How pretreated group, the maximum concentration of acetaminophen and the area under the plasma concentration-time curve were reduced about 58.4%, 56.7% and 55.4%. To further explain the results, liver microsomal suspensions were obtained from rats that were randomly divided into control and In-Chen-How pretreated group. The levels of CYP1A2 and CYP2E1 in hepatic microsomal protein from pretreated group were increased as compared to that from the control group. It indicated that In-Chen-How can stimulate the activity of CYP isozymes. The changes in the pharmacokinetics of acetaminophen resulting from the administration of In-Chen-How are related to an increase in metabolic activity of CYP1A2 and CYP2E1.
Acetaminophen ; administration & dosage ; blood ; pharmacokinetics ; Administration, Oral ; Analgesics, Non-Narcotic ; administration & dosage ; blood ; pharmacokinetics ; Animals ; Area Under Curve ; Artemisia ; chemistry ; Aryl Hydrocarbon Hydroxylases ; metabolism ; Cytochrome P-450 CYP1A2 ; metabolism ; Cytochrome P-450 CYP2E1 ; metabolism ; Drug Interactions ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Immunoblotting ; Male ; Metabolic Clearance Rate ; drug effects ; Microsomes, Liver ; drug effects ; enzymology ; Plants, Medicinal ; chemistry ; Random Allocation ; Rats ; Rats, Wistar

OBJECTIVETo investigate the changes of the activity of both protein kinase A and C and the mechanisms of antipyretic action of Guizhi decoction.

METHODThe fever responses were observed after combination injection of H-89 (a selective inhibitor of PKA) and calphostin C (a selective inhibitor of PKC), and oral pretreatment of Guizhi decoction in fever rats induced by an intra-cerebroventricular (icv) injection of an EP3 agonist, and both PKA and PKC activity in hypothalamus were measured in rats pretreated with Guizhi decoction and vehicle using isotopic tracing assay.

RESULTThe rise in rat body temperature was inhibited by H-89, Calphostin C, and Guizhi decoction, moreover, pretreatment with Guizhi decoction reduced PKA activity obviously. PKC activity in model rats exhibited a tendency to drop compared with that of control group, Oral administration of Guizhi decoction in large dose inhibited the response significantly, while the low dose of Guzhi decoction has no effect on PKC.

CONCLUSIONBoth PKA and PKC may participate in the mechanism of fever induction by EP3 agonist. The decrease of PKA and PKC may contribute to the antipyretic action of Guizhi decoction, some isoenzyme of PKC may play a role in the fever production.

Analgesics, Non-Narcotic ; pharmacology ; Animals ; Cinnamomum aromaticum ; chemistry ; Cyclic AMP-Dependent Protein Kinases ; metabolism ; Dinoprostone ; analogs & derivatives ; Dose-Response Relationship, Drug ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacology ; Fever ; chemically induced ; enzymology ; Hypothalamus ; enzymology ; Male ; Plants, Medicinal ; chemistry ; Protein Kinase C ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Receptors, Prostaglandin E ; agonists ; Receptors, Prostaglandin E, EP3 Subtype

OBJECTIVECapsaicin transfersomes were prepared and its quality specifications were evaluated.

METHODCapsaicin transfersomes were prepared by high shear dispersing machine and evaluated on the entrapment efficiency, drugs release rate and in vitro skin permeation.

RESULTCapsaicin transfersomes is composed of single unilamellar vesicles, with average size of 150.6 nm. Capsaicin entrapment efficiency achieved 96.7% while concentration of lecithin used was 8%. cumulative release amount of capsaicin was in direct proportion to the ethanol concentration in the medium. The in vitro rate cumulative penetration rate of capsaicin was higher in transfersomes than in cream and suspension in rats. Adomen skin cumulative penetration rate in vitro of capsaicin transfersomes in mouse was significantly higher than that from rat and men. In the same way,cumulative penetration rate in vitro of capsaicin transfersomes through abdomen skin epidermal membrance was significantly higher than that with derma and full skin in men.

CONCLUSIONEntrapment efficiency of capsaicin transfersomes reached 96.7%, meeting the criterion of China pharmacopia( > 80%), skin penetration of capsaicin was enhanced by a capsaicin transfersomes preparation and was affected by diverse characters and levels of skin.

Administration, Cutaneous ; Analgesics, Non-Narcotic ; administration & dosage ; pharmacokinetics ; Animals ; Capsaicin ; administration & dosage ; pharmacokinetics ; Drug Carriers ; Drug Delivery Systems ; methods ; Humans ; In Vitro Techniques ; Male ; Mice ; Particle Size ; Phosphatidylcholines ; administration & dosage ; chemistry ; pharmacology ; Rats ; Skin ; drug effects ; metabolism ; Skin Absorption ; drug effects

Large doses of acetaminophen (APAP) could cause oxidative stress and tissue damage through production of reactive oxygen/nitrogen (ROS/RNS) species and quinone metabolites of APAP. Although ROS/RNS are known to modify DNA, the effect of APAP on DNA modifications has not been studied systematically. In this study, we investigate whether large doses of APAP can modify the nuclear DNA in C6 glioma cells used as a model system, because these cells contain cytochrome P450-related enzymes responsible for APAP metabolism and subsequent toxicity (Geng and Strobel, 1995). Our results revealed that APAP produced ROS and significantly elevated the 8-oxo- deoxyguanosine (8-oxodG) levels in the nucleus of C6 glioma cells in a time and concentration dependent manner. APAP significantly reduced the 8- oxodG incision activity in the nucleus by decreasing the activity and content of a DNA repair enzyme, Ogg1. These results indicate that APAP in large doses can increase the 8-oxodG level partly through significant reduction of Ogg1 DNA repair enzyme.
Acetaminophen/*metabolism ; Analgesics, Non-Narcotic/*metabolism ; Animals ; Cell Line, Tumor ; DNA/metabolism ; DNA Damage ; DNA Glycosylases/*metabolism ; DNA Repair ; Deoxyguanosine/chemistry/*metabolism ; Glioma/*metabolism ; Glutathione/metabolism ; Humans ; Rats ; Reactive Nitrogen Species/metabolism ; Reactive Oxygen Species/metabolism