Metabolic and Hormonal Alterations in Cats with Hepatic Lipidosis

Programming of metabolic and autoimmune diseases in canine and feline: linkage to the gut microbiome

Metabolic and autoimmune disorders have long represented challenging health problems because of their growing prevalence in companion animals. The gut microbiome, made up of trillions of microorganisms, is implicated in multiple physiological and pathological processes. Similar to human beings, the complicated microbiome harbored in the gut of canines and felines emerges as a key factor determining a wide range of normal and disease conditions. Evidence accumulated from recent findings on canine and feline research uncovered that the gut microbiome is actively involved in host metabolism and immunity. Notably, the composition, abundance, activity, and metabolites of the gut microbiome are all elements that shape clinical outcomes concerning metabolism and immune function. This review highlights the implications of the gut microbiome for metabolic disorders (obesity, diabetes, and hepatic lipidosis) and autoimmune diseases (inflammatory bowel disease, osteoarthritis, asthma, and myasthenia gravis) in canine and feline animals, providing novel strategies and therapeutic targets for the prevention and treatment of pet diseases.

Dietary choline, but not L-carnitine, increases circulating lipid and lipoprotein concentrations, without affecting body composition, energy expenditure or respiratory quotient in lean and obese male cats during weight maintenance

Introduction

Due to the involvement in one-carbon metabolism and lipid mobilization, choline and L-carnitine supplementation have been recommended to minimize hepatic lipid accumulation and support fat oxidation, respectively. This study investigated the lipotropic benefits of choline or L-carnitine supplementation in lean and obese cats maintaining body weight (BW).

Methods

Lean [n = 9; body condition score (BCS): 4-5/9] and obese (n = 9; BCS: 8-9/9) adult male neutered colony cats were used in a replicated 3 x 3 complete Latin square design. Treatments included choline (378 mg/kg BW0.67), L-carnitine (200 mg/kg BW) and control (no supplement). Treatments were supplemented to the food for 6 weeks each, with a 2-week washout between treatments. Cats were fed once daily to maintenance energy requirements, and BW and BCS were assessed weekly. Fasted blood collection, indirect calorimetry, and dual-energy X-ray absorptiometry occurred at the end of each treatment period. Serum was analyzed for cholesterol (CHOL), high-density lipoprotein CHOL (HDL-C), triglycerides (TAG), non-esterified fatty acids (NEFA), glucose, creatinine (CREAT), urea, alkaline phosphatase (ALP) and alanine aminotransferase (ALT). Very low-density lipoprotein CHOL (VLDL) and low-density lipoprotein CHOL (LDL-C) were calculated. Data were analyzed using proc GLIMMIX, with group and period as random effects, and treatment, body condition, and their interaction as fixed effects, followed by a Tukey's post-hoc test when significance occurred.

Results

Cats supplemented choline had lower food intake (P = 0.025). Treatment did not change BW, BCS and body composition (P > 0.05). Obese cats had greater ALP, TAG, and VLDL, and lower HDL-C compared to lean cats (P < 0.05). Choline resulted in greater CHOL, HDL-C, LDL-C and ALT (P < 0.05). L-carnitine resulted in lower CREAT (P = 0.010). Following the post-hoc test, differences between treatment means were not present for ALP (P = 0.042). No differences were found for glucose, urea or NEFA (P > 0.05). Obese cats had a lower fed respiratory quotient (RQ), regardless of treatment (P = 0.045). Treatment did not affect fed or fasted RQ and energy expenditure (P > 0.05).

Discussion

Choline appeared to increase circulating lipid and lipoprotein concentrations regardless of body condition, likely through enhanced lipid mobilization and hepatic elimination. Neither dietary choline or L-carnitine altered body composition or energy metabolism in the lean or obese cats, as compared to control.

Endoplasmic reticulum stress as a key mechanism in stunted growth of seawater rainbow trout (Oncorhynchus mykiss)

BACKGROUND

Rainbow trout (Oncorhynchus mykiss) is a salmonid species with a complex life-history. Wild populations are naturally divided into freshwater residents and sea-run migrants. Migrants undergo an energy-demanding adaptation for life in seawater, known as smoltification, while freshwater residents display these changes in an attenuated magnitude and rate. Despite this, in seawater rainbow trout farming all fish are transferred to seawater. Under these circumstances, weeks after seawater transfer, a significant portion of the fish die (around 10%) or experience growth stunting (GS; around 10%), which represents an important profitability and welfare issue. The underlying causes leading to GS in seawater-transferred rainbow trout remain unknown. In this study, we aimed at characterising the GS phenotype in seawater-transferred rainbow trout using untargeted and targeted approaches. To this end, the liver proteome (LC-MS/MS) and lipidome (LC-MS) of GS and fast-growing phenotypes were profiled to identify molecules and processes that are characteristic of the GS phenotype. Moreover, the transcription, abundance or activity of key proteins and hormones related to osmoregulation (Gill Na+, K + -ATPase activity), growth (plasma IGF-I, and liver igf1, igfbp1b, ghr1 and ctsl) and stress (plasma cortisol) were measured using targeted approaches.

RESULTS

No differences in Gill Na+, K + -ATPase activity and plasma cortisol were detected between the two groups. However, a significant downregulation in plasma IGF-I and liver igf1 transcription pointed at this growth factor as an important pathomechanism for GS. Changes in the liver proteome revealed reactive-oxygen-species-mediated endoplasmic reticulum stress as a key mechanism underlying the GS phenotype. From the lipidomic analysis, key observations include a reduction in triacylglycerols and elevated amounts of cardiolipins, a characteristic lipid class associated with oxidative stress, in GS phenotype.

CONCLUSION

While the triggers to the activation of endoplasmic reticulum stress are still unknown, data from this study point towards a nutritional deficiency as an underlying driver of this phenotype.

Effect of ursodeoxycholic acid on glycemic markers: A systematic review and meta-analysis of clinical trials

Ursodeoxycholic acid (UDCA) is widely used to treat liver diseases; however, its potential effect on metabolic parameters has been poorly investigated. Additionally, owing to divergent data, the objective of this meta-analysis was to evaluate the effect of UDCA on glycemic parameters in clinical trials. Clinical trials investigating the impact of UDCA treatment on glycemic markers were searched in PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases (from inception to April 16, 2018). A random-effects model and generic inverse variance method were used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. A weighted random-effects meta-regression was performed to evaluate the impact of potential confounders on glycemic parameters. Meta-analysis of seven studies comprising eight treatment arms revealed a significant reduction of fasting glucose levels following UDCA therapy (WMD: -3.30 mg/dL, 95% CI: -6.36, -0.24, p = 0.034; I² = 28.95%). Also, meta-analysis of two treatment arms indicated a significant reduction of glycated hemoglobin (HbA1c) concentrations (WMD: -0.41% mg/dL, 95% CI: -0.81, -0.01, p = 0.042; I² = 0%). Additionally, meta-analysis of four treatment arms also revealed a significant reduction in plasma insulin levels (WMD: -1.50 mg/dL, 95% CI: -2.81, -0.19, p = 0.025; I² = 67.90%) but not significant effect HOMA-IR (WMD: -0.20 mg/dL, 95% CI: -0.42, 0.01, p = 0.057; I² = 85.34%). Results of this meta-analysis showed that UDCA significantly reduces fasting plasma glucose, HbA1c, and insulin concentrations suggesting a positive impact on glucose homeostasis.

Hepatic lipidosis: Clinical review drawn from collective effort

Practical relevance: Hepatic lipidosis (HL) is the most common form of liver dysfunction in cats. If recognized early and treated appropriately, the prognosis is good; if not, the prognosis is grave. Clinical challenges: Distinguishing HL as idiopathic or secondary is critical since the presence of a concurrent disease affects the therapeutic plan and the prognosis.

AUDIENCE

Despite the unique and severe nature of a cat's response to anorexia and the complexity of the metabolic changes underlying this condition, the clinical acumen and technical ability to effectively diagnose and treat HL are readily available to all small animal practitioners. Patient group: Although many species develop a 'fatty liver', the cat is one of relatively few species that suffer from HL. The classic presentation is that of an overweight cat that stops eating for days to weeks, losing weight in the process. Equipment: Abdominal ultrasound is frequently employed in the diagnostic work-up of an anorectic cat; ultrasonographic findings often support a presumptive diagnosis, provide samples for cytology and, perhaps most importantly, help identify concurrent conditions that must be addressed for therapeutic success. All of the equipment necessary for essential nutritional intervention in an anorectic cat is readily available and easily affordable. Evidence base: The material for this review draws heavily on a relatively large number of original studies, excellent reviews by recognized experts, and informative communication with experienced clinicians, hence the term 'collective effort'.

Prognostic markers in feline hepatic lipidosis: a retrospective study of 71 cats

Feline hepatic lipidosis (HL) is a common, potentially life-threatening disease resulting from prolonged anorexia and increased catabolism. This retrospective study included cats diagnosed with HL based on liver cytology or histopathology (years 2004-2015), and aimed to identify clinical and laboratory parameters associated with mortality. The study included 71 cats (47 females and 24 males) and 85 control cats with non-HL diseases. Most HL cats (90 per cent) were mixed breed, neutered (70; 99 per cent), female (47; 66 per cent), indoor cats (56; 79 per cent), fed dry commercial diets (44 cats; 62 per cent), and with a median age of 7.5 years (range 1.5-16.0). Common primary conditions included gastrointestinal diseases, pancreatitis and cholangiohepatitis (31 cats; 44 per cent) and stressful events (14; 20 per cent). HL was idiopathic in 20 cats (28 per cent). The overall mortality was 38 per cent (27/71 cats). Older age, as well as dullness, weakness, ptyalism, hypoproteinaemia, hypoalbuminaemia, increased serum creatine kinase activity, hypocholesterolaemia and hepatic failure at presentation were significantly (P≤0.033) associated with mortality. The primary disease was unassociated with mortality. Worsening hypoalbuminaemia, hyperammonaemia, hyperbilirubinaemia, electrolyte disorders, and occurrence of cavitary effusions or hypotension during hospitalisation were significantly (P≤0.045) associated with mortality. A decrease of serum β-hydroxybutyrate during hospitalisation was significantly (P=0.01) associated with survival, likely reflecting improvement in the catabolic state. The identified risk factors may be therapeutic targets.

Sex specific differences in hepatic and plasma lipid profiles in healthy cats pre and post spaying and neutering: relationship with feline hepatic lipidosis

BACKGROUND

A link between lipid metabolism and disease has been recognized in cats. Since hepatic lipidosis is a frequent disorder in cats, the aim of the current study was to evaluate liver and plasma lipid dimorphism in healthy cats and the effects of gonadectomy on lipid profiling. From six female and six male cats plasma and liver lipid profiles before and after spaying/neutering were assessed and compared to five cats (three neutered male and two spayed female) diagnosed with hepatic lipidosis.

RESULTS

Intact female cats had a significantly lower level of plasma triacylglycerides (TAG) and a higher liver level of the long chain polyunsaturated fatty acid arachidonic acid (AA) compared to their neutered state. Both male and female cats with lipidosis had a higher liver, but not plasma TAG level and an increased level of plasma and liver sphingomyelin compared to the healthy cats.

CONCLUSION

Although lipid dimorphism in healthy cats resembles that of other species, intact female cats show differences in metabolic configuration that could predispose them to develop hepatic lipidosis. The increased sphingomyelin levels in cats with lipidosis could suggest a potential role in the pathogenesis of hepatic lipidosis in cats.

Feline Hepatic Lipidosis

Feline hepatic lipidosis (FHL) is a common and potentially fatal liver disorder. Although the pathophysiologic mechanisms of FHL remain elusive, there is an imbalance between the influx of fatty acids from peripheral fat stores into the liver, de novo liposynthesis, and the rate of hepatic oxidation and dispersal of hepatic TAG via excretion of very-low density lipoproteins. The diagnosis of FHL is based on anamnestic, clinical, and clinicopathologic findings, associated with diagnostic imaging of the liver, and cytology, or histological examination of liver biopsies. Fluid therapy, electrolyte correction and adequate early nutrition are essential components of the therapy for FHL.

Adrenal function in cats with cholestatic liver disease

Cats with cholestatic liver disease experience significant morbidity and mortality when they undergo invasive procedures under anesthesia. Although inadequate adrenal response might account for these outcomes, adrenal function in cats with cholestatic liver disease has not been documented, to our knowledge. The goal of our study was to describe adrenal function in these cats. Twenty-seven cats with a serum bilirubin >230 µmol/L (3 mg/dL) and serum alanine aminotransferase >2 times the upper limit of normal had pre– and 60-min post–adrenocorticotropic hormone (ACTH) cortisol analysis after administration of 5 µg/kg cosyntropin intravenously. The change in cortisol concentrations (delta cortisol) was calculated. Pre- and post-ACTH cortisol concentrations were compared to reference values. Pre-ACTH, post-ACTH, and delta cortisol values were compared between cats surviving to discharge or for 30 d postdischarge. Mean pre-ACTH cortisol levels (205 ± 113 nmol/L [7.4 ± 4.2 µg/dL]) and post-ACTH cortisol levels (440 ± 113 nmol/L [15.9 ± 4.1 g/dL]) in cholestatic cats were significantly greater than reference values in clinically normal cats. There was no association of pre- or post-ACTH cortisol with survival. Cats with a delta cortisol <179 nmol/L (6.5 µg/dL) were more likely to be non-survivors at 30 d post-discharge ( p = 0.037) than cats with delta cortisol >179 nmol/L (6.5 µg/dL). Results indicate that cats with cholestasis have high basal and ACTH-stimulated cortisol values. A delta cortisol <179 nmol/L (6.5 µg/dL) defines a population of cats that have decreased 30-d survival.

Metabolic Effects of Obesity and Its Interaction with Endocrine Diseases

Obesity in pet dogs and cats is a significant problem in developed countries, and seems to be increasing in prevalence. Excess body fat has adverse metabolic consequences, including insulin resistance, altered adipokine secretion, changes in metabolic rate, abnormal lipid metabolism, and fat accumulation in visceral organs. Obese cats are predisposed to endocrine and metabolic disorders such as diabetes and hepatic lipidosis. A connection likely also exists between obesity and diabetes mellitus in dogs. No system has been developed to identify obese pets at greatest risk for development of obesity-associated metabolic diseases, and further study in this area is needed.

Changes in fatty acid composition in tissue and serum of obese cats fed a high fat diet

Background

Obesity and overweight have been frequently observed in dogs and cats in recent years as in humans. The compositions of fatty acids (FAs) in the accumulated lipids in tissues of obese animals may have important roles in the process and mechanisms related to the onset of metabolic disorders. The purpose of this study was to evaluate the effects of a high fat (HF) diet, which contained a higher proportion of saturated FAs, on FA metabolism and distribution in obese cats.

Cats (N = 12) were divided into control diet group (crude fat; 16.0 %) (n = 4) or a high fat (HF) diet group (crude fat; 23.9 %) (n = 8). The HF diet contained up to 60 % of calories from fat and was rich in stearic acid. Blood samples were collected at 0, 2, 4 and 6 weeks after the feeding. Adipose and liver tissues were collected at the 6^th week after feeding. We performed analysis of histological findings and fatty acid composition in serum and tissues.

Results

Body weights of the cats significantly increased in the HF group. The increased activities of hepatic enzymes and the accumulation of lipid droplets were found in hepatocytes in the HF group at the 6^th week after feeding.

In this study, the stearic acid (C18:0)-rich HF diet contained less oleic acid (C18:1n-9) and more linoleic acid (C18:2n-6) than the control. However, the composition of oleic acid in the liver was higher, and those of stearic acid and linoleic acid were lower in the HF group at the 6^th week after feeding. The higher oleic acid:stearic acid ratio suggests an increase in the conversion from saturated FA to mono-unsaturated FAs, which may reflect the hepatic storage of FAs as a relatively harmless form.

Conclusion

The stearic acid-rich HF diet increased hepatic lipid accumulation accompanied by the increased of hepatic oleic acid, increased serum oleic acid and activation of hepatic enzymes. These findings could be an important sign of early stages of dyslipidemia and hepatic damage. Also, the higher oleic acid:stearic acid ratio might be related to the increased activity of SCD-1, which suggests that the stearic acid-rich HF diet evoked hepatic lipogenesis in the feline liver.

Peculiarities of one-carbon metabolism in the strict carnivorous cat and the role in feline hepatic lipidosis

Research in various species has indicated that diets deficient in labile methyl groups (methionine, choline, betaine, folate) produce fatty liver and links to steatosis and metabolic syndrome, but also provides evidence of the importance of labile methyl group balance to maintain normal liver function. Cats, being obligate carnivores, rely on nutrients in animal tissues and have, due to evolutionary pressure, developed several physiological and metabolic adaptations, including a number of peculiarities in protein and fat metabolism. This has led to specific and unique nutritional requirements. Adult cats require more dietary protein than omnivorous species, maintain a consistently high rate of protein oxidation and gluconeogenesis and are unable to adapt to reduced protein intake. Furthermore, cats have a higher requirement for essential amino acids and essential fatty acids. Hastened use coupled with an inability to conserve certain amino acids, including methionine, cysteine, taurine and arginine, necessitates a higher dietary intake for cats compared to most other species. Cats also seemingly require higher amounts of several B-vitamins compared to other species and are predisposed to depletion during prolonged inappetance. This carnivorous uniqueness makes cats more susceptible to hepatic lipidosis.

Coagulation in hepatobiliary disease

OBJECTIVE

To review the pathogenesis and clinical consequences of coagulation abnormalities accompanying hepatobiliary disorders and to highlight the need for further studies to characterize these derangements and their treatment options in small animal patients.

DATA SOURCES

Veterinary and human medical literature: original research articles, scientific reviews, consensus statements, and recent texts.

SUMMARY

The liver plays an important role in the production and clearance of many components of coagulation. A wide range of hemostatic derangements can occur in patients with hepatobiliary disease including alterations in platelet number and function, coagulation factor levels, anticoagulants, vascular endothelial function, and fibrinolysis. As these hemostatic alterations include both pro- and anticoagulation pathways, the net result is often a rebalanced hemostatic system that can be easily disrupted by concurrent conditions resulting in either clinical bleeding or thrombosis. Conventional coagulation tests are inadequate at identifying the spectrum of coagulation alterations occurring in patients with hepatobiliary disease, but their evaluation is necessary to assess bleeding risk and provide prognostic information. A paucity of information exists regarding the treatment of the coagulation derangements in small animals with hepatobiliary disease. Extrapolation from human studies provides some information about potential treatment options, but further studies are warranted in this area to elucidate the best management for coagulation abnormalities in dogs and cats with hepatobiliary disease.

CONCLUSION

Hepatobiliary disease can have profound effects on coagulation function leading to hypercoagulable or hypocoagulable states. Overall coagulation status with hepatobiliary disease depends on both the type and severity of disease and the presence of associated complications.

Pharmacokinetics of pioglitazone in lean and obese cats

Pioglitazone is a thiazolidinedione insulin sensitizer that has shown efficacy in Type 2 diabetes and nonalcoholic fatty liver disease in humans. It may be useful for treatment of similar conditions in cats. The purpose of this study was to investigate the pharmacokinetics of pioglitazone in lean and obese cats, to provide a foundation for assessment of its effects on insulin sensitivity and lipid metabolism. Pioglitazone was administered intravenously (median 0.2 mg/kg) or orally (3 mg/kg) to 6 healthy lean (3.96 ± 0.56 kg) and 6 obese (6.43 ± 0.48 kg) cats, in a two by two Latin Square design with a 4-week washout period. Blood samples were collected over 24 h, and pioglitazone concentrations were measured via a validated high-performance liquid chromatography assay. Pharmacokinetic parameters were determined using two-compartmental analysis for IV data and noncompartmental analysis for oral data. After oral administration, mean bioavailability was 55%, t(1/2) was 3.5 h, T(max) was 3.6 h, C(max) was 2131 ng/mL, and AUC(0-∞) was 15 556 ng/mL · h. There were no statistically significant differences in pharmacokinetic parameters between lean and obese cats following either oral or intravenous administration. Systemic exposure to pioglitazone in cats after a 3 mg/kg oral dose approximates that observed in humans with therapeutic doses.

The Inappetent Hospitalised Cat: clinical approach to maximising nutritional support

PRACTICAL RELEVANCE

Inappetence is one of the most common presenting complaints in clinically ill cats requiring hospitalisation. When prolonged, poor food intake can lead to malnutrition and may be associated with impaired metabolic function, immunosuppression, compromised wound healing, and increased morbidity and mortality. It is important to recognise that inappetence or anorexia is always secondary to another condition, and that treatment goals should be targeted at the primary condition. The current emphasis in the nutritional support of hospitalised inappetent cats is to provide more effective means of increasing nutritional intake--for example, by initiating enteral nutrition via feeding tubes-- rather than rely solely on traditional approaches such as increasing palatability of foods or using appetite-stimulating drugs.

CLINICAL CHALLENGES

Cats that are ill enough to require hospitalisation are at increased risk of becoming malnourished because of the combined catabolic effects of their disease and poor nutritional intake. This article highlights some of the problems encountered in treating inappetent cats and discusses a clinical approach to providing better nutritional support.

PATIENT GROUP

Inappetence and anorexia are associated with a myriad of clinical conditions in cats and can be seen in individuals of any age or breed.

EQUIPMENT

Provision of nutritional support to cats may involve the use of feeding tubes such as naso-oesophageal or oesophagostomy tubes. In cases where enteral nutrition is not feasible (eg, cats with gastrointestinal failure), parenteral nutrition should be considered.

EVIDENCE BASE

Various studies have documented the high prevalence of inappetence or anorexia in clinically ill cats. Additional studies have linked poor food intake in cats with serious sequelae such as immunosuppression and hepatic lipidosis. More recently, techniques for providing more effective nutritional support, such as oesophagostomy tubes, have been clinically evaluated and shown to be associated with minimal complications.

Short-term fasting induces intra-hepatic lipid accumulation and decreases intestinal mass without reduced brush-border enzyme activity in mink (Mustela vison) small intestine

For many mammalian species short-term fasting is associated with intestinal atrophy and decreased digestive capacity. Under natural conditions, strictly carnivorous animals often experience prey scarcity during winter, and they may therefore be particularly well adapted to short-term food deprivation. To examine how the carnivorous gastrointestinal tract is affected by fasting, small-intestinal structure, brush-border enzyme activities and hepatic structure and function were examined in fed mink (controls) and mink that had been fasted for 1-10 days. During the first 1-2 days of fasting, intestinal mass decreased more rapidly than total body mass and villus heights were reduced 25-40%. In contrast, tissue-specific activity of the brush-border enzymes sucrase, maltase, lactase, aminopeptidase A and dipeptidylpeptidase IV increased 0.5- to 1.5-fold at this time, but returned to prefasting levels after 6 days of fasting. After 6-10 days of fasting there was a marked increase in the activity of hepatic enzymes and accumulation of intra-hepatic lipid vacuoles. Thus, mink may be a useful model for studying fasting-induced intestinal atrophy and adaptation as well as mechanisms involved in accumulation of intra-hepatic lipids following food deprivation in strictly carnivorous domestic mammals, such as cats and ferrets.

Angiotensin-converting enzyme inhibitors in the therapy of renal diseases

Renal diseases, especially chronic renal failure (CRF), are common in canine and feline medicine. The renin-angiotensin-aldosterone system (RAAS) plays a pivotal role in these conditions in the development of renal lesions and the progression of kidney dysfunction. Angiotensin-converting enzyme inhibitors (ACEI) are currently considered as the most efficient agents in therapeutic strategies. The benefit of an ACEI treatment can be explained by at least three mechanisms: ACEI limit systemic and glomerular capillary hypertension, have an antiproteinuric effect, and retard the development of glomerulosclerosis and tubulointerstitial lesions. These effects have been studied in dogs and cats, and there is now some evidence to support the recommendation of ACEI therapy in dogs and cats with CRF. Nevertheless the prescription of ACEI in such patients should take into account the potential influence of renal impairment on ACEI disposition, and adverse effects on the renal function itself (especially hypotension and acute reductions in glomerular filtration rate). The risk of drug interaction with diuretics, nonsteroidal anti-inflammatory drugs and anesthetics, should not be overestimated. Furthermore, hypotension may occur in patients on a low sodium diet.

Plasma lipids, lipoprotein composition and profile during induction and treatment of hepatic lipidosis in cats and the metabolic effect of one daily meal in healthy cats

Anorexia in obese cats may result in feline hepatic lipidosis (FHL). This study was designed to determine plasma lipids and lipoprotein profiles in queens at different stages during experimental induction of FHL (lean, obese, FHL), and after 10 weeks of treatment. Results were compared with those obtained from lean queens of same age fed the same diet but at a maintenance level, once a day. Hepatic lipidosis led to an increase in plasma triacylglycerol (TG), very low density lipoprotein (VLDL) and low density lipoprotein (LDL), and an enrichment of LDL with TG and of high density lipoprotein (HDL) with cholesterol, suggesting that VLDL secretion is enhanced, VLDL and LDL catabolism is lowered, and lipoprotein exchanges are impaired in FHL. This study also showed that cholesterolaemia is increased in cats fed at a dietary rhythm of one meal per day compared to ad libitum feeding.