Evidence that early life exposure to acetaminophen causes neurodevelopmental injury in susceptible children has mounted for more than a decade. Evidence is diverse, including extensive work with laboratory animals, otherwise unexplained associations, factors associated with the metabolism of acetaminophen, and some limited studies in humans. Although evidence has reached an overwhelming level and has been reviewed in detail recently, some controversy remains. In this narrative review, some of those controversies are evaluated. First, the associations through time between acetaminophen use and the prevalence of neurodevelopmental disorders are considered. A systematic review reveals that the use of acetaminophen in the pediatric population was never tracked carefully, but historical events that affected use of the drug were documented and are sufficient to establish apparent correlations with changes in the prevalence of neurodevelopmental disorders. Second, problems with exclusive reliance on results from meta-analyses of large datasets and from studies involving small time frames of drug exposure are reviewed. Third, the potential bias in a study designed to separate the role of vaccines and acetaminophen in the induction of autism spectrum disorder (Autism 2008;12:293-307) is carefully evaluated. Finally, evidence demonstrating why some children are susceptible to acetaminophen-induced neurodevelopmental injury is examined. It is concluded that, at least among the factors considered, there is no valid rationale for controversy regarding the conclusion that early life exposure to acetaminophen causes neurodevelopmental injury in susceptible babies and small children.

A growing body of literature suggests a causative relationship between severe adverse neurological outcomes and early life exposure to paracetamol (acetaminophen) in the presence of oxidative stress. Review of the literature revealed that, although its use is not regularly monitored, paracetamol has achieved near universal acceptance, with exposure in some pediatric populations exceeding 90%. In addition, use of the drug as well as associated adverse outcomes may have risen as a result of pharmaceutical advertising rather than need, and inappropriate use of the drug, both in terms of dose and indication, is widespread. These findings indicate that many clinicians and patients do not, at the present time, evenly weigh the potential risks with the potential benefits of paracetamol exposure early in life. Although retrospective studies might be envisioned to further address the neurodevelopmental risks of paracetamol use during early development, in silico simulations demonstrated that such studies can be thwarted by very high rates of use of the drug combined with associations between paracetamol use and oxidative stressors that act as cofactors in the induction of neurodevelopmental injury. These findings suggest that, despite persistent uncertainty, clinicians and patients should be more aware of available information pointing toward the potential dangers for neurodevelopment of early life exposure to paracetamol. Most importantly, health care workers need to provide a more balanced view, weighing both risks and benefits, when providing advice for patients regarding paracetamol use during periods of brain development.

Acetaminophen use during pregnancy and early childhood was accepted in the 1970s, but is now a subject of considerable concern. Careful analysis shows that initial acceptance of the drug was based on false assumptions and ignorance of the impact of the drug on brain development. Fourteen studies now indicate that prenatal exposure to acetaminophen is associated with neurodevelopmental problems. Based on corrections for confounding factors applied to the analyses of available data, it can be concluded that prenatal exposure to acetaminophen causes statistically significant risks of one subtype of autism spectrum disorder (ASD), developmental delays, and attention deficit hyperactivity disorder. In contrast, data regarding postnatal exposure to acetaminophen are limited, and several factors impede a classic multivariate analysis of data to resolve the issue. However, circumstantial evidence regarding postnatal exposure to the drug is abundant, and it can be concluded beyond a reasonable doubt that postnatal exposure to acetaminophen in susceptible children is responsible for many if not most cases of ASD. Circumstantial evidence includes at least three otherwise unexplained temporal relationships, data from laboratory animal studies, several miscellaneous and otherwise unexplained correlations, and the lack of alternative suspects that fit the evidence-derived profile.

Although widely believed to be safe for use in infants and children when used as directed, increasing evidence indicates that early life exposure to paracetamol (acetaminophen) may cause long-term neurodevelopmental problems. Further, recent studies in animal models demonstrate that cognitive development is exquisitely sensitive to paracetamol exposure during early development. In this study, evidence for the claim that paracetamol is safe was evaluated using a systematic literature search. Publications on PubMed between 1974 and 2017 that contained the keywords “infant” and either “paracetamol” or “acetaminophen” were considered. Of those initial 3096 papers, 218 were identified that made claims that paracetamol was safe for use with infants or children. Of these, a total of 103 papers were identified as sources of authority for the safety claim, and 36 of those contained actual experiments designed to test safety. The 36 experiments described had a median follow-up time of 24 hours, and none monitored neurodevelopment. Further, no trial considered total exposure to drug since birth, eliminating the possibility that the effects of drug exposure on long-term neurodevelopment could be accurately assessed. On the other hand, abundant and sufficient evidence was found to conclude that paracetamol does not induce acute liver damage in babies or children when used as directed.

Paracetamol or acetaminophen (N-acetyl-para-aminophenol, APAP) is an analgesic and antipy-retic drug commonly used worldwide, implicated in numerous intoxications due to overdose, and causing serious liver damage. APAP can cross the blood-brain barrier and affects brain function in numerous ways including pain signals, temperature regulation, neuroimmune response and emotional behavior; however, its effect on adult neurogenesis has not been thoroughly investi-gated. We analyze the effect of APAP overdose (750 mg/kg/day), for 3 and 4 consecutive days and after cessation of APAP administration for 6 and 15 days, on cell proliferation and survival in two relevant neurogenic zones: the subgranular zone of the dentate gyrus and the hypothalamus. The involvement of liver damage (plasma transaminases), neuronal activity (c-Fos) and astroglia (GFAP) was also evaluated. Our results indicated that repeated APAP overdoses were associated with inhibition of adult neurogenesis in a context of elevated liver transaminase levels, neuronal hyperactivity and as-trogliosis. These effects were partially reversed after cessation of APAP administration for 6 and 15 days. In conclusion, these results suggest that APAP overdose impairs adult neurogenesis in the hip-pocampus and hypothalamus, a fact that may contribute to the effects of APAP on brain function.

Gastric emptying rate (GER) may impact diabetes and obesity in humans and could provide a method to reduce canine weight gain. Starch, the most common source of carbohydrates (CHOs) in pet food, is classified as rapidly or slowly digestible, or resistant to digestion. This study investigated starch source effects in commercial extruded dog foods on the GER of 11 healthy adult Siberian Huskies (5.63±0.72 years; mean±SEM). Test diets were classified as traditional, grain-free, whole-grain, and vegan. Dogs received each diet once, a glucose control twice, and acetaminophen (Ac) as a marker for GER in a randomized, partially-replicated, 6x6 Latin square design. Pre- and post-prandial blood samples were collected at 16 timepoints from -15 to 480 minutes. Serum Ac concentrations were assessed via standard spectrophotometric assays and fitted with a mathematical model to estimate parameters of GER. Data was analyzed using a repeated measures ANOVA, followed by a Tukey-Kramer post-hoc test when significant (p<0.05). More total emptying (p= 0.0430) occurred at faster rate (p=0.0668) in dogs fed the grain-free diet, which contained the lowest total starch (34.03 ± 0.23%) and highest resistant starch (0.52 ± 0.007%). This research may benefit future diet formulations to reduce the prevalence of canine weight gain.

Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenol in green tea. In this study, the effects of dietary EGCG on oxidative stress and the metabolism and toxicity of acetaminophen in liver were investigated. Rats were fed the diets with (0.54 %) or without EGCG supplementation for four weeks and were then intraperitoneally injected with acetaminophen (1g/kg). Results showed EGCG lowered hepatic oxidative stress and cytochrome P450 (CYP) 1A2, 2E1, and 3A, and UDP-glucurosyltransferase activities prior to acetaminophen injection. After acetaminophen challenge, the elevations in plasma alanine aminotransferase activity and histological changes in liver were ameliorated by EGCG treatment. EGCG reduced acetaminophen-induced apoptosis by increasing the Bax/Bcl2 ratio in liver. EGCG mildly increased autophagy by increasing the LC3B II/I ratio. Lower hepatic acetaminophen-glutathione and acetaminophen-protein adducts contents were observed after EGCG treatment. EGCG increased glutathione peroxidase and NAD(P)H quinone 1 oxidoreductase activities and reduced organic anion-transporting polypeptides 1a1 expression in liver after acetaminophen treatment. Our results indicate that EGCG may lower oxidative stress and reduce the metabolism and toxicity of acetaminophen. The reductions in CYP-mediated acetaminophen bioactivation and uptake transporter, as well as enhanced antioxidant enzyme activity, may limit the accumulation of toxic products in liver and thus lower hepatotoxicity

The liver diseases are posing serious threat to human health associated with abusive use of allopathy medicines, especially in developing economies like Pakistan. The strengthening of detoxification system using natural products might be a suitable option to minimize the liver problems. In this current research, Zingiber officinale and Azadirachta indica were evaluated for their hepatoprotective role. For the purpose, 20 Sprague Dawley rats were equally divided into four groups i.e., negative control, paracetamol positive control, 2.5% ginger and 2% neem powder, respectively. During 42 days study, the levels of bilirubin and liver enzymes significantly elevated due to liver damage. Although, the values dropped (20-25%) in treatment group. Serum glucose and serum lipid profile increased in positive control group, but reduced (5-10%) in both ginger and neem groups. The serum protein profile declined in liver damage group, however, improved (~5%) in treatment groups. The hematological parameters slightly declined in liver damage group, but increased in ginger and neem groups. Moreover, the white blood cells differential count and renal parameters showed abnormal values in liver damage group, but improved after treatment. This study is promising and highlighted the hepato-protective role of neem and ginger that may open several avenues of research.

Autism spectrum disorder (ASD) is a neurodevelopmental disease characterized by persistent deficits in social interaction and communication, repetitive movements, abnormal focusing on objects, or activity that can significantly affect the quality of life of the afflicted. Brain neuronal and glial cells have been implicated. It has a genetic component but can also be triggered by environmental factors or drugs. For example, prenatal exposure to valproic acid (VPA) or acetaminophen (APAP) or ingestion of propionic acid (PPA) can increase the risk of ASD. Recently, epigenetic influences on ASD have been brought to the forefront of investigations on the etiology, prevention, and treatment of this disorder. Epigenetics refers to DNA modifications that alter gene expression without making any changes to the DNA sequence. Although an increasing number of pharmaceuticals and environmental chemicals are being implicated in the etiology of ASD, here we specifically focus on the molecular influence of the above-mentioned drugs on epigenetic alterations in neuronal and glial cells and their potential connection to ASD. It is concluded that a better understanding of these phenomena can lead to more effective interventions in ASD.

We report the isolation of two novel degrading bacterial strains active against the potential environmental pollutant acetamino-phen/paracetamol. Streptomyces Chrestomyceticus (RS2) and Streptomyces Flavofuscus (M33) collected from El-Natrun Valley, Egypt, water, sediment, and sand samples were taxonomically characterized via conidiophores morphologic characterization under Trans-mission Electron Microscope (TEM). Genotypic identification, done based on their 16S rRNA gene sequence analysis followed by BLAST alignment and deposited on the NCBI as 2 novel strains. The phylogenetic tree was constructed using an appropriate software. Acetaminophen degradation-products chemical structure was identified by GC/LC MS. The biological antimicrobial activity of some selected acetaminophen degradation-products extracts and derived compounds was examined against panel of test micro-organisms and found to be have high anti-microbial effect. In addition, in silico cheminformatics Swiss ADMET evaluation of these selected deg-radation extract for gastric absorption, distribution, hepatic metabolism, renal excretion as well as distribution to CNS and finally not mutagenic/teratogenic or genotoxic virtually. In vitro cytotoxic activity of these selected bio-degradation products was performed against HepG2 and MCF7 cancer cell lines, revealing that M33 and RS2 extract effect on acetaminophen/paracetamol bio-degradation products are potentially safe with higher IC50 on HepG2 and MCF7, in comparison to acetaminophen/paracetamol with IC50 of 108.5 μg/ml. Moreover, the in vivo acute oral single dose toxicity experiment was conducted, being compared with acetamino-phen/paracetamol to confirm that the bio-degradation products have lower toxicity than acetaminophen in vivo and in silico.

We hereby describe an efficient method for the preparation of a series of new 1-substituted 1,2,3-triazole-based acetaminophen derivatives through a clean, good-yielding, simple, and expeditious procedure based on the O-propargylation reaction of the acetaminophen (APAP) obtained from expired commercial tablets and the CuBr(PPh3)3-catalyzed Huisgen reaction be-tween O-propargylated APAP and diverse organoazides prepared from commercially available anilines as available starting reagents. An interesting nitric oxide-releasing 1,2,3-triazole hybrid of APAP was also obtained easily using the developed method. The structures of the designed hybrid compounds, which are expected to be pharmacologically active, were fully characterized by FT-IR, 1H- and 13C-NMR and are reported for the first time. According to the in-silico studies performed in this work and literature analysis, these hybrids are interesting models in search of new pharmacological nontoxic agents endowed with anti-inflammatory and anticancer properties.