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Glyco-metabolic deteriorations are the most limiting adverse reactions to antipsychotics in the long term. They have been incompletely investigated and the properties of antipsychotics that determine their magnitude are not clarified.
To rank antipsychotics by the magnitude of glyco-metabolic alterations and to associate it to their pharmacological and chemical properties, we conducted a network meta-analysis.
We searched PubMed, Embase, and Psycinfo on 10 September 2020. We selected studies containing the endpoint-baseline difference or the distinct values of at least one outcome among glucose, HbA1c, insulin, HOMA-IR, triglycerides, total/HDL/LDL cholesterols. Of 2094 articles, 46 were included in network meta-analysis. Study quality was assessed by the RoB 2 and ROBINS-I tools. Mean differences (MD) were obtained by random-effects network meta-analysis; relations between MD and antipsychotic properties were analyzed by linear regressions. Antipsychotic properties investigated were acidic and basic pKa, polar surface area, polarizability, and occupancies of D2, H1, M1, M3, α1A, α2A, 5-HT1A, 5-HT2A, 5-HT2C receptors.
We meta-analyzed 46 studies (11 464 patients); on average, studies lasted 15.47 weeks, patients had between 17.68 and 61.06 years of mean age and 61.64% were males. Olanzapine and clozapine associated with greater deteriorations, aripiprazole and ziprasidone with smaller deteriorations. Higher polarizability and 5-HT1A receptor occupancy were associated with smaller deteriorations, H1, M1, and M3 receptor occupancies with larger deteriorations.
Drug rankings may guide antipsychotic switching toward metabolically safer drugs. Mechanistic insights may suggest improvements for combination therapies and drug development. More data are required regarding newer antipsychotics.
It is uncertain if long-term levels of low-density lipoprotein-cholesterol (LDL-C) affect cognition in middle age. We examined the association of LDL-C levels over 25 years with cognitive function in a prospective cohort of black and white US adults.
Lipids were measured at baseline (1985–1986; age: 18–30 years) and at serial examinations conducted over 25 years. Time-averaged cumulative LDL-C was calculated using the area under the curve for 3,328 participants with ≥3 LDL-C measurements and a cognitive function assessment. Cognitive function was assessed at the Year 25 examination with the Digit Symbol Substitution Test [DSST], Rey Auditory Visual Learning Test [RAVLT], and Stroop Test. A brain magnetic resonance imaging (MRI) sub-study (N = 707) was also completed at Year 25 to assess abnormal white matter tissue volume (AWMV) and gray matter cerebral blood flow volume (GM-CBFV) as secondary outcomes.
There were 15.6%, 32.9%, 28.9%, and 22.6% participants with time-averaged cumulative LDL-C <100 mg/dL, 101–129 mg/dL, 130–159 mg/dL, and ≥160 mg/dL, respectively. Standardized differences in all cognitive function test scores ranged from 0.16 SD lower to 0.09 SD higher across time-averaged LDL-C categories in comparison to those with LDL-C < 100 mg/dL. After covariate adjustment, participants with higher versus lower time-averaged LDL-C had a lower RAVLT score (p-trend = 0.02) but no differences were present for DSST, Stroop Test, AWMV, or GM-CBFV.
Cumulative LDL-C was associated with small differences in memory, as assessed by RAVLT scores, but not other cognitive or brain MRI measures over 25 years of follow-up.
Although higher plasma cholesterol concentrations have not been reported to be associated with increased stroke risk, cholesterol lowering has been reported to decrease this risk. This decrease can be achieved with statins, which are well-tolerated, provided they are not given to patients with active liver or muscle diseases. Statin treatment in addition to a healthy lifestyle is recommended for the primary prevention of ischaemic stroke in patients with pre-existing coronary heart disease or other high-risk conditions such as diabetes and hypertension. Statins with intensive lipid-lowering effects are recommended for their positive influence on reducing the risks of stroke and cardiovascular events for patients with prior ischaemic stroke or TIA presumed to be of non-cardioembolic origin, even with an LDL-C level =100 mg/dL, with or without evidence of other clinical atherosclerotic cardiovascular diseases. Despite the good safety profile of statins, further studies are clarify safety in patients with prior cerebral haemorrhage and if they may increase brain haemorrhage to a small degree. PCSK9 inhibitors are advised, as add-on therapy to statins, for patients with a high cardiac risk not able to achieve an optimal LDL-C level, though studies with longer follow-up are needed
The aim of this study was to explore the effects and mechanisms of different starvation treatments on the compensatory growth of Acipenser dabryanus. A total of 120 fish (60·532 (sem 0·284) g) were randomly assigned to four groups (fasting 0, 3, 7 or 14 d and then refed for 14 d). During fasting, middle body weight decreased significantly with prolonged starvation. The whole-body and muscle composition, serum biochemical indexes, visceral indexes and digestive enzyme activities had been effected with varying degrees of changes. The growth hormone (GH) level in serum was significantly increased in 14D; however, insulin-like growth factor-1 (IGF-1) showed the opposite trend. The neuropeptide Y (npy) mRNA level in brain was significantly improved in 7D; peptide YY (pyy) mRNA level in intestine was significantly decreased during fasting. After refeeding, the final body weight, percentage weight gain, specific growth rate, feed intake, feed efficiency and protein efficiency ratio showed no difference between 0D and 3D. The changes of whole-body and muscle composition, serum biochemical indexes, visceral indexes and digestive enzyme activities had taken place in varying degrees. GH levels in 3D and 7D were significantly higher than those in the 0D; the IGF-1 content decreased significantly during refeeding. There was no significant difference in npy and pyy mRNA levels. These results indicated that short-term fasting followed by refeeding resulted in full compensation and the physiological and biochemical effects on A. dabryanus were the lowest after 3 d of starvation and 14 d of refeeding. Additionally, compensation in A. dabryanus may be mediated by appetite genes and GH, and the degree of compensation is also affected by the duration of starvation.
We investigated the impact of recent caffeine drinking on glucose and other biomarkers of cardiometabolic function under free-living conditions while also accounting for lifestyle and genetic factors that alter caffeine metabolism and drinking behaviour. Up to 447 794 UK Biobank participants aged 37–73 years in 2006–2010 provided a non-fasting blood sample, for genetic and biomarker measures, and completed questionnaires regarding sociodemographics, medical history and lifestyle. Caffeine drinking (yes/no) about 1 h before blood collection was also recorded. Multivariable regressions were used to examine the association between recent caffeine drinking and serum levels of glycated Hb, glucose, lipids, apo, lipoprotein(a) and C-reactive protein. Men and women reporting recent caffeine drinking had clinically and significantly higher glucose levels than those not recently drinking caffeine (P < 0·0001). Larger effect sizes were observed among those 55+ years of age and with higher adiposity and longer fasting times (P ≤ 0·02 for interactions). Significant CYP1A2 rs2472297×caffeine and MLXIPL rs7800944 × caffeine interactions on glucose levels were observed among women (P = 0·004), with similar but non-significant interactions in men. Larger effect sizes were observed among women with rs2472297 CC or rs7800944 CC genotypes than among rs2472297 T or rs7800944 T carriers, respectively. In summary, men and women drinking caffeine within about 1 h of blood draw had higher glucose levels than those not drinking caffeine. Findings were modified by age, adiposity, fasting time and genetic factors related to caffeine metabolism and drinking behaviour. Implications for clinical and population studies of caffeine-containing beverages and cardiometabolic health are discussed.
Replacing intake of SFA with PUFA reduces serum cholesterol levels and CVD risk. The effect on glycaemic regulation is, however, less clear. The main objective of the present study was to investigate the short-term effect of replacing dietary SFA with PUFA on glycaemic regulation. Seventeen healthy, normal-weight participants completed a 25-d double-blind, randomised and controlled two-period crossover study. Participants were allocated to either interventions with PUFA products or SFA products (control) in a random order for three consecutive days, separated by a 1·5-week washout period between the intervention periods. Glucose, insulin and TAG were measured before and after an oral glucose tolerance test. In addition, fasting total cholesterol, NEFA and plasma total fatty acid profile were measured before and after the 3-d interventions. Fasting and postprandial glucose, insulin, and TAG levels and fasting levels of NEFA and plasma fatty acid profile did not differ between the groups. However, replacing dietary SFA with PUFA significantly reduced total cholesterol levels by 8 % after 3 d (P = 0·002). Replacing dietary SFA with PUFA for only 3 d has beneficial cardio-metabolic effects by reducing cholesterol levels in healthy individuals.
n-3 Long-chain PUFA (LCPUFA) can improve cardiometabolic blood markers, but studies in children are limited. SNP in the FADS genes, which encode fatty acid desaturases, influence endogenous LCPUFA production. Moreover, SNP in genes that encode PPAR and apoE may modulate the effects of n-3 LCPUFA. We explored whether FADS polymorphisms were associated with blood cholesterol and TAG, insulin and glucose and whether polymorphisms in PPAR and APOE modified associations between FADS or n-3 LCPUFA status and the cardiometabolic blood markers. We measured fasting cholesterol and TAG, insulin, glucose and n-3 LCPUFA in 757 Danish 8–11-year-old children and genotyped SNP in FADS (rs1535 and rs174448), PPARG2 (rs1801282), PPARA (rs1800206) and APOE (rs7412+rs429358). Carriage of two FADS rs174448 major alleles was associated with lower TAG (P = 0·027) and higher HDL-cholesterol (P = 0·047). Blood n-3 LCPUFA was inversely associated with TAG and insulin in PPARG2 minor allele carriers and positively with LDL-cholesterol in major allele homozygotes (Pn-3 LCPUFA × rs180182 < 0·01). Associations between n-3 LCPUFA and cardiometabolic markers were not modified by APOE genotype (Pn-3 LCPUFA × APOE > 0·11), but interaction between FADS rs1535 and APOE showed that rs1535 major allele homozygotes who also carried APOE2 had higher HDL-cholesterol than all other genotype combinations (Prs1535 × APOE = 0·019, pairwise-P < 0·05). This indicates that FADS genotypes, which increase endogenous LCPUFA production, may beneficially affect children’s cardiometabolic profile in a partly APOE-dependent manner. Also, the degree to which children benefit from higher n-3 LCPUFA intake may depend on their PPARG2 genotype.
Kefir consumption has been demonstrated to improve lipid and cholesterol metabolism; however, our previous study identified that benefits vary between different commercial and traditional kefir. Here, we investigate the ability of pitched culture kefir, that is, kefir produced by a small number of specific strains, to recapitulate health benefits of a traditional kefir, in a diet-induced obesity mouse model, and examine how microbial composition of kefir impacts these benefits. Eight-week-old female C57BL/6 mice were fed a high-fat diet (40 % energy from fat) supplemented with one of five kefir varieties (traditional, pitched, pitched with no Lactobacillus, pitched with no yeast and commercial control) at 2 ml in 20 g of food for 8 weeks prior to analysis of plasma and liver lipid profiles, and liver gene expression profiles related to lipid metabolism. Both traditional and pitched kefir lowered plasma cholesterol by about 35 % (P = 0·0005) and liver TAG by about 55 % (P = 0·0001) when compared with commercial kefir despite no difference in body weight. Furthermore, pitched kefir produced without either yeast or Lactobacillus did not lower cholesterol. The traditional and pitched kefir with the full complement of microbes were able to impart corresponding decreases in the expression of the cholesterol and lipid metabolism genes encoding 3-hydroxy-3-methylglutaryl-coenzyme A reductase, PPARγ and CD36 in the liver. These results demonstrate that traditional kefir organisms can successfully be utilised in a commercial process, while highlighting the importance of microbial interactions during fermentation in the ability of fermented foods to benefit host health.
Mycoprotein consumption has been shown to improve acute postprandial glycaemic control and decrease circulating cholesterol concentrations. We investigated the impact of incorporating mycoprotein into the diet on insulin sensitivity (IS), glycaemic control and plasma lipoprotein composition. Twenty healthy adults participated in a randomised, parallel-group trial in which they consumed a 7 d fully controlled diet where lunch and dinner contained either meat/fish (control group, CON) or mycoprotein (MYC) as the primary source of dietary protein. Oral glucose tolerance tests were performed pre- and post-intervention, and 24 h continuous blood glucose monitoring was applied throughout. Fasting plasma samples were obtained pre- and post-intervention and were analysed using quantitative, targeted NMR-based metabonomics. There were no changes within or between groups in blood glucose or serum insulin responses, nor in IS or 24 h glycaemic profiles. No differences between groups were found for 171 of the 224 metabonomic targets. Forty-five lipid concentrations of different lipoprotein fractions (VLDL, LDL, intermediate-density lipoprotein and HDL) remained unchanged in CON but showed a coordinated decrease (7–27 %; all P < 0·05) in MYC. Total plasma cholesterol, free cholesterol, LDL-cholesterol, HDL2-cholesterol, DHA and n-3 fatty acids decreased to a larger degree in MYC (14–19 %) compared with CON (3–11 %; P < 0·05). Substituting meat/fish for mycoprotein twice daily for 1 week did not modulate whole-body IS or glycaemic control but resulted in changes to plasma lipid composition, the latter primarily consisting of a coordinated reduction in circulating cholesterol-containing lipoproteins.
Fruit intake is associated with lower risk of cardiometabolic diseases. However, effects of dried fruits on cardiometabolic health are not well researched. We investigated the effect of daily dried fruit consumption compared with a carbohydrate-rich snack on cardiometabolic disease risk factors in adults with increased cardiometabolic risk. A two-period randomised crossover trial was conducted in adults (n 55) with elevated BMI and at least one additional risk factor for cardiometabolic disease to compare the effects of consuming 3/4 cup/d mixed dried fruits (plums, figs, dates and raisins) or an energy- and carbohydrate-matched control snack for 4 weeks. The primary outcome was LDL-cholesterol; secondary outcomes included other lipids and lipoproteins, glucose and insulin, C-reactive protein, blood pressure and vascular stiffness. Linear mixed models were used for data analysis. Lipid and lipoprotein concentrations did not differ between conditions; however, dried fruit increased LDL-cholesterol (0·10 mmol/l, 95 % CI 0·01, 0·20) compared with baseline. Compared with the control, dried fruit increased mean fasting glucose (0·08 mmol/l, 95 % CI 0·005, 0·16; P = 0·038). Vascular outcomes, fasting insulin and C-reactive protein did not differ between conditions. Mean weight changes did not differ (P = 0·55) but tended to increase after both conditions (dried fruit 0·3 kg, 95 % CI –0·09, 0·65; control 0·4 kg, 95 % CI 0·01, 0·75). Thus, short-term daily consumption of a large portion of mixed dried plums, figs, dates and raisins, without structured dietary guidance, did not improve cardiometabolic risk factors, compared with carbohydrate-rich snacks, in adults with increased baseline cardiometabolic risk.
The aim of this study was to identify possible peripheral biological markers (both lipidic and hormonal) which can be easily used for the early detection of parasuicidal behaviour and to propose a predictive biological model of such behaviour. A case-control analytical study was undertaken at least 3 months after attempted suicide. Study was made of 128 patients who presented at the University General Hospital of Oviedo (Spain) with signs of self-intoxication. Lipidic and hormonal profiles were measured under basal conditions and comparison was made with a control group of healthy volunteer donors obtained from the Oviedo General Hospital blood bank. A discriminant analysis was later made with the aim of establishing a predictive biological model. This included the following variables: cholesterol, HDL-C, LDL-C and cortisol. Sensitivity and specificity were 62.5% and 65.6%, respectively. Replication and improvement of this model, through other prospective studies, could lead to the use of serum cholesterol and cortisol levels as inexpensive and readily available markers of suicide risk.
The aim of this study was to evaluate whether women with a history of violent suicide attempts have lower serum cholesterol concentrations than those who attempted suicide by non-violent methods. Our retrospective study used a case-control design to compare serum total cholesterol concentration, hematocrit, red blood cell count and body mass index (BMI) in women with a history of violent (n = 19) or non-violent (n = 51) suicide attempts and of non-suicidal controls (n = 70) matched by diagnosis and age. Analysis of covariance (ANCOVA) with age as the covariate was used to analyze differences in cholesterol levels in groups according to violence. Violence was found to be a significant factor (P = 0.016). Using the Scheffé test, a significant difference (P = 0.011) was revealed between the group of violent and non-violent suicide attempters and between the violent suicide attempters and the control group. Patients with a violent suicidal attempt have significantly lower cholesterol levels than patients with non-violent attempts and the control subjects. Our findings suggest that suicide attempts should not be considered a homogenous group. They are consistent with the theory that low levels of cholesterol are associated with increased tendency for impulsive behavior and aggression and contribute to a more violent pattern of suicidal behavior.
Epidemiological studies, animal studies, and clinical studies yielded conflicting results concerning a supposed association between increased risk for suicide and violence, and low serum cholesterol levels. Until now, no data has been available for patients with schizophrenia, a disorder with a well-known increased risk of violence. Correlations of serum cholesterol levels at admission and measures of violence were investigated in 103 consecutively admitted patients (44 males, 59 females) of a general psychiatric admission unit. Seventy subjects were diagnosed as suffering from schizophrenia or schizoaffective disorder (ICD-10 F 20, F25), and 33 were diagnosed as suffering from non-psychotic disorders (mainly personality disorders). The level of total exhibited violence during the inpatient treatment period was measured in each patient by the Modified Overt Aggression Scale (MOAS), the Social Dysfunction and Aggression Scale (SDAS), the Staff Observation Aggression Scale (SOAS), and the Violence Scale (VS). Correlations of all violence measures were high (0.75–0.90), but no correlation was found with cholesterol levels, neither for psychotic nor for non-psychotic subjects, neither for men nor for women. The hypothesis of associations of violence and cholesterol levels is not supported by the data.
The purpose of this chronoepidemiologic study was to investigate the time-relationships between the yearly variations in occurrence of violent suicide in Belgium and the yearly variations in various biochemical, metabolic and immune variables in the Belgian population. The weekly mean number of deaths due to violent suicide for all of Belgium for the period 1979–1987 was computed. Twenty-six normal volunteers had monthly blood samplings during one calendar year for assays of plasma L-tryptophan (L-TRP), competing amino acids (CAA), and melatonin levels, maximal [3H]paroxetine binding to platelets, serum total cholesterol, calcium, magnesium, and soluble interleukin-2 receptor concentrations, and number of CD4+ T, CD8+ T and CD20+ B lymphocytes. The annual rhythm in violent suicide rate is highly significantly synchronized with the annual rhythms in L-TRP, [3H]paroxetine binding, cholesterol, calcium, magnesium, CD20+ B cells, and CD4+/CD8+ ratio; the mean peak (violent suicide, [3H]paroxetine binding) or nadir (all other variables) occurs around 3 May. There were significant inverse time-relationships between the time series of violent suicide rate and L-TRP, L-TRP/CAA ratio, total cholesterol, calcium and magnesium, CD4+/CD8+ T cell ratio and number of CD20+ B cells. Maximal [3H]paroxetine binding to platelets was significantly and positively related to the time series of violent suicide. An important part (56.4%) of the variance in mean weekly number of violent suicide rate was explained by the time series of L-TRP, cholesterol and melatonin.
It has been suggested that low serum cholesterol interferes with brain serotonergic functioning, which results in increased suicidal and aggressive tendencies. To test this hypothesis we investigated the relationship between serum cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglyceride levels, and serotonin uptake by blood platelets in 17 healthy men aged 39.5 ± 10.2 years. Platelet serotonin uptake and serum lipids were assayed concomitantly for each individual. Serum cholesterol levels and other serum lipid levels did not correlate with serotonin uptake by platelets at the concentration of 2 × 10−5 M (a concentration within the maximal uptake capacity range). The results indicate no influence of cholesterol on serotonin uptake, as opposed to some investigators who suggested that high risk of suicide and aggressiveness in hypocholesterolemic individuals is related to impaired serotonin transport.
The question of whether hypocholesterolemic treatment is associated with increased mortality due to suicide, violence and car accidents is controversial and of great importance. We investigated the effect of hypocholesterolemic dietary and drug therapy on dysphoric emotions. Twenty-five hypocholesterolemic men were started on a 3-month dietary modification plan; those who showed unsatisfactory cholesterol reduction were given, in addition, a hypocholesterolemic drug for up to 1 year. Lipid profile and change in dysphoric emotions were measured. During the whole period, a negative correlation was found between cholesterol level and depression. During the dietary period, a significant improvement in depression and guilt with no change in lipid profile was noted. Drug therapy significantly reduced cholesterol levels, with a trend toward increased depression (after 3 months) and a significant increase in aggression and guilt (after 1 year). We conclude that changes in dysphoric emotions occurring during hypocholesterolemic therapy cannot be completely explained by the changes in cholesterol levels.
Suicidal behavior is a major health risk in psychiatric disorders, especially in schizophrenia, and up to 10% patients will commit suicide. The neurobiology of suicide is still unclear. Suicidality has been related to a decreased central serotonergic (5-hydroxytryptamine, 5-HT) function and reduced cholesterol levels. Platelet 5-HT was used as a peripheral marker of the central serotonergic synaptosomes. The hypothesis was that suicidal patients in the first episode of psychosis will have different serum cholesterol and platelet 5-HT concentrations than non-suicidal patients in the first episode of psychosis. The aim of this study was to evaluate serum cholesterol and platelet 5-HT concentrations in suicidal and non-suicidal men in the first episode of psychosis and in healthy male controls. Venous blood samples were collected within 24 hours of admission, and serum cholesterol and platelet 5-HT were determined enzymatically and fluorimetrically. Platelet 5-HT and serum cholesterol concentrations were significantly lower in suicidal than in non-suicidal patients in the first episode of psychosis, and than in healthy controls. Our results suggest that lower concentrations of serum cholesterol and platelet 5-HT in patients with the first episode of psychosis might be useful biological markers of suicidality.
Low levels of blood cholesterol have been found in some children with autism spectrum disorders (ASD). Psychotropic medications, commonly used by people with ASD and people with intellectual disabilities (ID) are frequently associated with altered metabolic profiles.
We aimed to compare metabolic features of adults with ASD or ID with those of a community-based population.
Subjects and methods
Data on blood fasting glucose (FBG), lipid profile, liver enzyme profile, TSH, BMI, medications and diagnoses of 80 adults with ASD, 77 adults with ID and 828 control adults were drawn from medical charts/database. Candidates that used glucose or lipid lowering medications were not included.
Total-cholesterol levels of people with ASD and ID were significantly lower than those of the controls (168.3 ± 32.78, 168.2 ± 32.91, 185.4 ± 40.49 mg/dL, respectively, P < 0.001) but after adjusting for gender, age and BMI and using Bonferroni correction, the significance was lost. Compared to controls, ASD and ID had significantly lower FBG (by –14.45 ± 1.81, –14.58 ± 1.54 mg/dl, respectively; P < 0.001 for both) and liver enzymes, despite using psychotropic medications.
Discussion and conclusion
In contrast to other psychiatric patients receiving similar medications, people with ASD and ID have unaltered lipid profiles and lower glucose and liver enzyme levels compared to a community-based population.
The in utero and immediate postnatal environments are recognized as critical windows of developmental plasticity where offspring are highly susceptible to changes in the maternal metabolic milieu. Maternal hypercholesterolemia (MHC) is a pathological condition characterized by an exaggerated rise in maternal serum cholesterol during pregnancy which can program metabolic dysfunction in offspring, including dysregulation of hepatic lipid metabolism. Although there is currently no established reference range MHC, a loosely defined cutoff point for total cholesterol >280 mg/dL in the third trimester has been suggested. There are several unanswered questions regarding this condition particularly with regard to how the timing of cholesterol exposure influences hepatic lipid dysfunction and the mechanisms through which these adaptations manifest in adulthood. Gestational hypercholesterolemia increased fetal hepatic lipid concentrations and altered lipid regulatory mRNA and protein content. These early changes in hepatic lipid metabolism are evident in the postweaning environment and persist into adulthood. Further, changes to hepatic epigenetic signatures including microRNA (miR) and DNA methylation are observed in utero, at weaning, and are evident in adult offspring. In conclusion, early exposure to cholesterol during critical developmental periods can predispose offspring to the early development of nonalcoholic fatty liver disease (NAFLD) which is characterized by altered regulatory function beginning in utero and persisting throughout the life cycle.
Foamy, whitish appearance of the pyloric caeca, reflecting elevated lipid content, histologically visible as hypervacuolation, is frequently observed in Atlantic salmon fed high-plant diets. Lipid malabsorption syndrome (LMS) is suggested as term for the phenomenon. Earlier studies have shown that insufficient supply of phospholipids may cause similar symptoms. The objective of the present study was to strengthen knowledge on the role of choline, the key component of phosphatidylcholine, in development of LMS as well as finding the dietary required choline level in Atlantic salmon. A regression design was chosen to be able to estimate the dietary requirement level of choline, if found essential for the prevention of LMS. Atlantic salmon (456 g) were fed diets supplemented with 0, 392, 785, 1177, 1569, 1962, 2354, 2746 and 3139 mg/kg choline chloride. Fish fed the lowest-choline diet had pyloric caeca with whitish foamy surface, elevated relative weight, and the enterocytes were hypervacuolated. These characteristics diminished with increasing choline level and levelled off at levels of 2850, 3593 and 2310 mg/kg, respectively. The concomitant alterations in expression of genes related to phosphatidylcholine synthesis, cholesterol biosynthesis, lipid transport and storage confirmed the importance of choline in lipid turnover in the intestine and ability to prevent LMS. Based on the observations of the present study, the lowest level of choline which prevents LMS and intestinal lipid hypervacuolation in post-smolt Atlantic salmon is 3·4 g/kg. However, the optimal level most likely depends on the feed intake and dietary lipid level.