Supporting Machine Learning Model in the Treatment of Chronic Pain.

Conventional therapy options for chronic pain are still insufficient and patients most frequently request alternative medical treatments, such as medical cannabis. Although clinical evidence supports the use of cannabis for pain, very little is known about the efficacy, dosage, administration methods, or side effects of widely used and accessible cannabis products. A possible solution could be given by pharmacogenetics, with the identification of several polymorphic genes that may play a role in the pharmacodynamics and pharmacokinetics of cannabis. Based on these findings, data from patients treated with cannabis and genotyped for several candidate polymorphic genes (single-nucleotide polymorphism: SNP) were collected, integrated, and analyzed through a machine learning (ML) model to demonstrate that the reduction in pain intensity is closely related to gene polymorphisms. Starting from the patient's data collected, the method supports the therapeutic process, avoiding ineffective results or the occurrence of side effects. Our findings suggest that ML prediction has the potential to positively influence clinical pharmacogenomics and facilitate the translation of a patient's genomic profile into useful therapeutic knowledge.

Untargeted NMR Metabolomics Reveals Alternative Biomarkers and Pathways in Alkaptonuria.

Alkaptonuria (AKU) is an ultra-rare metabolic disease caused by the accumulation of homogentisic acid (HGA), an intermediate product of phenylalanine and tyrosine degradation. AKU patients carry variants within the gene coding for homogentisate-1,2-dioxygenase (HGD), which are responsible for reducing the enzyme catalytic activity and the consequent accumulation of HGA and formation of a dark pigment called the ochronotic pigment. In individuals with alkaptonuria, ochronotic pigmentation of connective tissues occurs, leading to inflammation, degeneration, and eventually osteoarthritis. The molecular mechanisms underlying the multisystemic development of the disease severity are still not fully understood and are mostly limited to the metabolic pathway segment involving HGA. In this view, untargeted metabolomics of biofluids in metabolic diseases allows the direct investigation of molecular species involved in pathways alterations and their interplay. Here, we present the untargeted metabolomics study of AKU through the nuclear magnetic resonance of urine from a cohort of Italian patients; the study aims to unravel molecular species and mechanisms underlying the AKU metabolic disorder. Dysregulation of metabolic pathways other than the HGD route and new potential biomarkers beyond homogentisate are suggested, contributing to a more comprehensive molecular signature definition for AKU and the development of future adjuvant treatment.

The Pharmacogenetics of Cannabis in the Treatment of Chronic Pain.

BACKGROUND: The increase in the medical use of cannabis has revealed a number of beneficial effects, a variety of adverse side effects and great inter-individual variability. Association studies connecting consumption, addiction and side effects related to recreational cannabis use have led to the identification of several polymorphic genes that may play a role in the pharmacodynamics and pharmacokinetics of cannabis. METHOD: In total, 600 patients treated with cannabis were genotyped for several candidate polymorphic genes (single-nucleotide polymorphism; SNP), encoding receptors CNR1 and TRPV1; for the ABCB1 transporter; for biotransformation, bioactivation and biosynthesis; and CYP3A4, COMT and UGT2B7 conjugation. RESULTS: Three polymorphic genes (ABCB1, TRPV1 and UGT2B7) were identified as being significantly associated with decline in pain after treatment with cannabis. Patients simultaneously carrying the most favourable allele combinations showed a greater reduction (polygenic effect) in pain compared to those with a less favourable combination. Considering genotype combinations, we could group patients into good responders, intermediate responders and poor or non-responders. Results suggest that genetic makeup is, at the moment, a significant predictive factor of the variability in response to cannabis. CONCLUSIONS: This study proves, for the first time, that certain polymorphic candidate genes may be associated with cannabis effects, both in terms of pain management and side effects, including therapy dropout. SIGNIFICANCE: Our attention to pharmacogenetics began in 2008, with the publication of a first study on the association between genetic polymorphisms and morphine action in pain relief. The study we are presenting is the first observational study conducted on a large number of patients involving several polymorphic candidate genes. The data obtained suggest that genetic makeup can be a predictive factor in the response to cannabis therapy and that more extensive and planned studies are needed for the opening of new scenarios for the personalization of cannabis therapy.

Transient hypothyroxinemia of prematurity and histological chorioamnionitis.

BACKGROUND: Transient hypothyroxinaemia of prematurity (THOP) is a common condition of preterm infants whose causes remain unclear. We tested the hypothesis that THOP is associated with histological chorioamnionitis (HCA). METHODS: Whole blood T4 and TSH concentrations on day 4 and at 40 weeks' postmenstrual age (rtx-T4 and rtx-TSH), placental histology and illness severity were prospectively evaluated in 155 very low birth weight (VLBW) infants. RESULTS: HCA-positive infants showed significantly decreased blood total T4 concentrations on day 4, as compared to the HCA-negative population (P<0.0001), along with comparable TSH, rtx-T4, and rtx-TSH blood concentrations. None of the infants showed evidence of hypothyroidism during the study. A total T4 < or = 4.4 microg/dL on postnatal day 4 identified HCA-positive newborns with 90.8%, sensitivity, 94.7%, specificity, 96.7% positive predictive and 85.7% negative predictive values. HCA (OR: 32.19; 95% CI: 8.95-115.64), birth weight < or = 880 g (OR: 4.1; 1.15-14.64), and RDS (OR: 3.71, 95% CI: 1.13-12.25) were independently associated with evidence of hypothyroxinaemia on day 4. CONCLUSION: Our findings indicate a previously un-recognized relationship between HCA and THOP, hence suggesting a predominant role for a fetal systemic inflammatory response syndrome in the pathogenesis of THOP.

Simple non-radiochemical HPLC-linked method for screening for purine metabolism disorders using dried blood spot.

BACKGROUND: Pathologies associated with rare inherited disorders affecting purine metabolic pathways range from renal failure to neurological dysfunction and immunodeficiency. The disorders are usually diagnosed by measuring enzyme activities in hemolysates. A non-radiochemical HPLC-linked method is described for simultaneous determination of the activities of hypoxanthine-guanine phosphoribosyltransferase (HPRT: E.2.4.2.8.), adenine phosphoribosyltransferase (APRT: E.2.4.2.7.), adenosine deaminase (ADA: E.3.5.4.4.) and purine nucleoside phosphorylase (PNP: E.2.4.2.1.) in dried blood spots. METHOD: 7-mm-diameter blood spots stored at 4 degrees C or room temperature were transferred to an Eppendorf tube and eluted with 500-microl 0.1 mol/l Tris-HCl buffer, pH 7.4. The eluate was added to substrate solutions and incubated at 37 degrees C. Reaction products were analysed by HPLC. RESULTS AND CONCLUSIONS: The enzyme activities tested in spot eluates were similar to those in erythrocyte lysates from the same subjects. None of the enzymatic activities tested were significantly affected by different storage temperatures. The main advantages of the proposed method are small blood volume required, easy sample collection and transfer, and accurate results. The method is therefore suitable for screening inborn errors of purine metabolism even in newborns.

Biochemical and molecular study of mentally retarded patient with partial deficiency of hypoxanthine-guanine phosphoribosyltransferase.

Nucleotide metabolism was studied in erythrocytes of a mentally retarded child and family members. Partial hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency was found in the propositus and an asymptomatic maternal uncle. Studies in crude lysates demonstrated decreased apparent V(max) and slightly decreased apparent K(m) for hypoxanthine in both HPRT-deficient subjects. Genomic DNA analysis revealed a single nucleotide change with leucine-147 to phenylalanine substitution in both subjects; mother and grandmother were heterozygous carriers of the same defect. This new variant has been termed HPRT(Potenza). Increased erythrocyte concentration of NAD and rate of synthesis by intact erythrocytes were found in the patient; increased activities of nicotinic acid phosphoribosyltransferase (NAPRT) and NAD synthetase (NADs) were demonstrated in erythrocyte lysates, with normal apparent K(m) for their substrates and increased V(max). These alterations were not found in any member of the family, including the HPRT-deficient uncle. These findings show multiple derangement of nucleotide metabolism associated with partial HPRT deficiency. The enzyme alteration was presumably not the cause of neurological impairment since no neurological symptoms were found in the HPRT-deficient uncle, whereas they were present in the propositus' elder brother who had normal HPRT activity.