Recreational Drugs and the Risk of Hepatocellular Carcinoma.

Recreational or aesthetic drug use is a distinctive behavior of humans, principally attested in the last century. It is known that recreational and illegal drugs are major contributors to the universal morbidity rate worldwide. Many of these substances have a well-established hepatotoxic potential, causing acute or chronic liver injury, liver fibrosis and cirrhosis, but their implications for hepatocellular carcinoma or other varieties of liver tumors are little known. In this article, we perform an extensive literature review, aiming to provide updated information about recreational drug use and the risk of developing liver tumors. Khat use and pyrrolizidine alkaloid consumption (present in some natural plants) have been linked to liver cirrhosis. Kava intake is associated with different liver tumors in animal models but not in humans. Cannabis' potential to accelerate liver fibrosis in chronic hepatitis is controversial according to the existing data. Cigarette smoking is an important contributor to hepatocellular carcinoma, and anabolic androgen steroids are well-defined causes of a variety of liver cancers and other hepatic tumors. Long-term follow-up studies of subjects who have developed injuries in association with the use of recreational drugs are warranted so as to better define the risk of developing hepatocellular carcinoma in association with these substances and, thus, to implement health care policies to combat this preventable cause of cancer.

N-Acetylcysteine for Preventing Acetaminophen-Induced Liver Injury: A Comprehensive Review.

Aims: N-Acetylcysteine (NAC) is used as an antidote in acetaminophen (APAP) overdose to prevent and mitigate drug-induced liver injury (DILI). Our objective was to systematically review evidence of the use of NAC as a therapeutic option for APAP overdose and APAP-related DILI in order to define the optimal treatment schedule and timing to start treatment. Methods: Bibliographic databases (PubMed, Web of Science, Embase, and MEDLINE) were searched for retrospective and prospective cohort studies, case series, and clinical trials. The prespecified primary outcomes were DILI-related mortality, hepatotoxicity, and adverse events (AEs). Results: In total, 34 studies of NAC usage in APAP-related DILI cases with 19,580 patients were identified, of which 2,376 patients developed hepatotoxicities. The mortality rate across different studies ranged from 0 to 52%. Large variability of NAC regimens was found, i.e., intravenous (I.V.) (100-150 mg/kg) and oral (70-140 mg/kg), and length of treatment varied-12, 24, or 48 h for I.V. regimen and 72 h for oral administration. The timing of initiation of NAC treatment showed different results in terms of occurrence of hepatotoxicity and mortality; if started within 8 h and no more than 24 h from APAP overdose, either intravenously or orally, NAC administration was efficacious in terms of mortality. The most frequent AEs reported were anaphylactic reactions, followed by cutaneous AEs for the IV route and intestinal AEs for the oral one. Conclusion: NAC improves hepatotoxicity and reduces mortality. Timing of treatment, ranging from 8 to 24 h from APAP overdose, regardless of the regimen or route of administration, is important to prevent or minimize liver damage, particularly in children and in elderly and obese patients.

Identification of New Toxicity Mechanisms in Drug-Induced Liver Injury through Systems Pharmacology.

Among adverse drug reactions, drug-induced liver injury presents particular challenges because of its complexity, and the underlying mechanisms are still not completely characterized. Our knowledge of the topic is limited and based on the assumption that a drug acts on one molecular target. We have leveraged drug polypharmacology, i.e., the ability of a drug to bind multiple targets and thus perturb several biological processes, to develop a systems pharmacology platform that integrates all drug-target interactions. Our analysis sheds light on the molecular mechanisms of drugs involved in drug-induced liver injury and provides new hypotheses to study this phenomenon.

Methionine Cycle Rewiring by Targeting miR-873-5p Modulates Ammonia Metabolism to Protect the Liver from Acetaminophen.

Drug-induced liver injury (DILI) development is commonly associated with acetaminophen (APAP) overdose, where glutathione scavenging leads to mitochondrial dysfunction and hepatocyte death. DILI is a severe disorder without effective late-stage treatment, since N-acetyl cysteine must be administered 8 h after overdose to be efficient. Ammonia homeostasis is altered during liver diseases and, during DILI, it is accompanied by decreased glycine N-methyltransferase (GNMT) expression and S-adenosylmethionine (AdoMet) levels that suggest a reduced methionine cycle. Anti-miR-873-5p treatment prevents cell death in primary hepatocytes and the appearance of necrotic areas in liver from APAP-administered mice. In our study, we demonstrate a GNMT and methionine cycle activity restoration by the anti-miR-873-5p that reduces mitochondrial dysfunction and oxidative stress. The lack of hyperammoniemia caused by the therapy results in a decreased urea cycle, enhancing the synthesis of polyamines from ornithine and AdoMet and thus impacting the observed recovery of mitochondria and hepatocyte proliferation for regeneration. In summary, anti-miR-873-5p appears to be an effective therapy against APAP-induced liver injury, where the restoration of GNMT and the methionine cycle may prevent mitochondrial dysfunction while activating hepatocyte proliferative response.

Fatal acute hepatitis after sequential treatment with levofloxacin, doxycycline, and naproxen in a patient presenting with acute Mycoplasma pneumoniae infection.

BACKGROUND: The diagnosis of drug-induced liver injury relies on comprehensive clinical assessments due to the absence of an established biomarker or pathognomonic features of liver histology. However, prompt recognition of a culprit drug as the cause of liver injury is the most important aspect in the management of hepatotoxicity. CASE SUMMARY: A 63-year-old white male (85 kg) was admitted because of community-acquired pneumonia with associated pericarditis and subclinical hepatitis, subsequently related to acute Mycoplasma pneumoniae infection (diagnostic positive immuno-globulin M enzyme immunoassay, on hospital days 5 and 20). The patient had received cisplatin and radiotherapy from March to May 2006, as treatment for pharyngolaryngeal squamous cell carcinoma T3N0M0 without subsequent evidence of localized or meta-static recurrent disease (last oncologic consultation, May 17, 2007). He reported alcohol ingestion until March 2006 but no known liver disease, blood transfusion, or exposure to mushrooms or industrial cleaning solvents. Results of serologic tests for viral and nonviral infectious hepatitis, iron and copper studies, and tests for autoantibodies were normal or negative. The patient became initially asymptomatic and fever disappeared following sequential treatment with levo-floxacin (500 mg BID), doxycycline (100 mg BID), and naproxen (500 mg TID). However, on hospital day 10 jaundice and a significant elevation (alanine aminotransferase, 1577 U/L; aspartate amino-transferase, 1754 U/L; alkaline phosphatase, 189 U/L) of serum transaminases appeared. Despite the discontinuation of all medication, the patient gradually deteriorated and died 27 days after admission due to acute fulminant hepatic failure. Autopsy revealed massive hepatic necrosis, inflammatory changes with presence of eosinophils, and cholestasis. An objective causality assessment scale (Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method scale) suggested that each of the 3 drugs could "probably" (score = 6) be related to the patient's fulminant hepatitis. The Naranjo Adverse Drug Reactions Probability Scale assessment for the same drugs indicated a "possible" causal relation (score = 2). CONCLUSION: We report a case of lethal hepatitis possibly/probably associated with levofloxacin, doxy-cycline, and naproxen in a patient with acute M pneumoniae infection.