Neurometabolic changes in a rat pup model of type C hepatic encephalopathy depend on age at liver disease onset.

Chronic liver disease (CLD) is a serious condition where various toxins present in the blood affect the brain leading to type C hepatic encephalopathy (HE). Both adults and children are impacted, while children may display unique vulnerabilities depending on the affected window of brain development.We aimed to use the advantages of high field proton Magnetic Resonance Spectroscopy (H MRS) to study longitudinally the neurometabolic and behavioural effects of Bile Duct Ligation (animal model of CLD-induced type C HE) on rats at post-natal day 15 (p15) to get closer to neonatal onset liver disease.

In vivo macromolecule signals in rat brain H-MR spectra at 9.4T: Parametrization, spline baseline estimation, and T relaxation times.

Purpose: Reliable detection and fitting of macromolecules (MM) are crucial for accurate quantification of brain short-echo time (TE) H-MR spectra. An experimentally acquired single MM spectrum is commonly used. Higher spectral resolution at ultra-high field (UHF) led to increased interest in using a parametrized MM spectrum together with flexible spline baselines to address unpredicted spectroscopic components.

Probiotics improve the neurometabolic profile of rats with chronic cholestatic liver disease.

Chronic liver disease leads to neuropsychiatric complications called hepatic encephalopathy (HE). Current treatments have some limitations in their efficacy and tolerability, emphasizing the need for alternative therapies. Modulation of gut bacterial flora using probiotics is emerging as a therapeutic alternative.

Late post-natal neurometabolic development in healthy male rats using H and P magnetic resonance spectroscopy.

Brain metabolism evolves rapidly during early post-natal development in the rat. While changes in amino acids, energy metabolites, antioxidants or metabolites involved in phospholipid metabolism have been reported in the early stages, neurometabolic changes during the later post-natal period are less well characterized. Therefore, we aimed to assess the neurometabolic changes in male Wistar rats between post-natal days 29 and 77 (p29-p77) using longitudinal magnetic resonance spectroscopy (MRS) in vivo at 9.

Contribution of macromolecules to brain H MR spectra: Experts' consensus recommendations.

Proton MR spectra of the brain, especially those measured at short and intermediate echo times, contain signals from mobile macromolecules (MM). A description of the main MM is provided in this consensus paper. These broad peaks of MM underlie the narrower peaks of metabolites and often complicate their quantification but they also may have potential importance as biomarkers in specific diseases.

Longitudinal osmotic and neurometabolic changes in young rats with chronic cholestatic liver disease.

Type C hepatic encephalopathy (type C HE) is increasingly suspected in children with chronic liver disease (CLD), and believed to underlie long-term neurocognitive difficulties. The molecular underpinnings of type C HE in both adults and children are incompletely understood. In the present study we combined the experimental advantages of in vivo high field H magnetic resonance spectroscopy with immunohistochemistry to follow longitudinally over 8 weeks the neurometabolic changes in the hippocampus of animals having undergone bile duct ligation as pups.

Longitudinal neurometabolic changes in the hippocampus of a rat model of chronic hepatic encephalopathy.

Background & Aims: The sequence of events in hepatic encephalopathy (HE) remains unclear. Using the advantages of in vivo 1H-MRS (9.4T) we aimed to analyse the time-course of disease in an established model of type C HE by analysing the longitudinal changes in a large number of brain metabolites together with biochemical, histological and behavioural assessment.

MRS studies of neuroenergetics and glutamate/glutamine exchange in rats: Extensions to hyperammonemic models.

In vivo Magnetic Resonance Spectroscopy is a useful tool to characterize brain biochemistry as well as its alteration in a large number of major central nervous system diseases. The present review will focus on the study of the glutamate-glutamine cycle, an important biochemical pathway in excitatory neurotransmission, analyzed using in vivo MRS of different accessible nuclei: H, C, N and P. The different methodological aspects of data acquisition, processing and absolute quantification of the MRS data for each nucleus will be presented, as well as the description of the mathematical modeling approach to interpret the MRS measurements in terms of biochemical kinetics.

Ammonia toxicity: from head to toe?

Ammonia is diffused and transported across all plasma membranes. This entails that hyperammonemia leads to an increase in ammonia in all organs and tissues. It is known that the toxic ramifications of ammonia primarily touch the brain and cause neurological impairment.

Creatine in the central nervous system: From magnetic resonance spectroscopy to creatine deficiencies.

Creatine (Cr) is an important organic compound acting as intracellular high-energy phosphate shuttle and in energy storage. While located in most cells where it plays its main roles in energy metabolism and cytoprotection, Cr is highly concentrated in muscle and brain tissues, in which Cr also appears to act in osmoregulation and neurotransmission. This review discusses the basis of Cr metabolism, synthesis and transport within brain cells.

H and P magnetic resonance spectroscopy in a rat model of chronic hepatic encephalopathy: in vivo longitudinal measurements of brain energy metabolism.

Chronic liver disease (CLD) leads to a spectrum of neuropsychiatric disorders named hepatic encephalopathy (HE). Even though brain energy metabolism is believed to be altered in chronic HE, few studies have explored energy metabolism in CLD-induced HE, and their findings were inconsistent. The aim of this study was to characterize for the first time in vivo and longitudinally brain metabolic changes in a rat model of CLD-induced HE with a focus on energy metabolism, using the methodological advantages of high field proton and phosphorus Magnetic Resonance Spectroscopy (H- and P-MRS).