Lipoprotein Synthesis Research Articles

Identification and characterization of the lipoprotein N-acyltransferase in Bacteroides

Members of the Bacteroidota compose a large portion of the human gut microbiota, contributing to overall gut health via the degradation of various polysaccharides. This process is facilitated by lipoproteins, globular proteins anchored to the cell surface by a lipidated N-terminal cysteine. Despite their importance, lipoprotein synthesis by these bacteria is understudied. In Escherichia coli, the α-amino-linked lipid of lipoproteins is added by the lipoprotein N-acyltransferase Lnt. Herein, we have identified a protein distinct from Lnt responsible for the same process in Bacteroides, named lipoprotein N-acyltransferase in Bacteroides (Lnb). Deletion of Lnb yields cells that synthesize diacylated lipoproteins, with impacts on cell viability and morphology, growth on polysaccharides, and protein composition of membranes and outer membrane vesicles (OMVs). Our results not only challenge the accepted paradigms of lipoprotein biosynthesis in gram-negative bacteria but also suggest the existence of a new family of lipoprotein N-acyltransferases.

Short-term effects of gastric bypass versus sleeve gastrectomy on high LDL cholesterol: The BASALTO randomized clinical trial

BackgroundThere has been a substantial increase in the use of laparoscopic sleeve gastrectomy (SG) to treat morbid obesity despite observational evidence demonstrating the superiority of Roux-en-Y gastric bypass (RYGB) for reducing low-density lipoprotein (LDL) cholesterol. The main aim was to ascertain whether high LDL cholesterol levels should be considered when selecting the most appropriate surgical procedure for each patient (RYGB or SG).MethodsIn this single-center, randomized clinical trial using intention-to-treat analysis, 38 patients with severe obesity and elevated levels of LDL cholesterol were randomly assigned to undergo RYGB or SG. The primary outcome was LDL cholesterol remission at 12 months, defined as LDL cholesterol < 3.36 nmol/l without lipid-lowering medications. Secondary outcomes included changes in weight, other comorbidities, qualitative lipoprotein traits, cholesterol esters, glycoproteins, cholesterol absorption and synthesis metabolites and complications.ResultsIntention-to-treat analysis revealed that LDL cholesterol remission occurred in 66.6% of RYGB patients compared to 27.8% of SG patients (p = 0.019). Among patients completing follow-up, RYGB demonstrated superior remission (80.0% vs. 29.4%, p = 0.005). Exclusive benefits of RYGB included a reduction in large, medium, and small LDL particles. Cholesterol absorption markers showed differential behavior after both techniques: campesterol (Δ −15.2 µg/mg, 95% CI −30.2 to −0.1) decreased after RYGB, and sitosterol (Δ 21.1 µg/mg, 95% CI 0.9 to 41.2), cholestanol (Δ 30.6 µg/mg, 95% CI 14.8 to 57.9) and campesterol (Δ 18.4 µg/mg, 95% CI 4.4 to 32.3) increased after SG. No differences in weight loss, cholesterol esters, glycoproteins, cholesterol synthesis metabolites or postoperative complications were observed between techniques.ConclusionIn conclusion, RYGB is superior to SG in terms of short-term of high LDL cholesterol remission. Furthermore, RYGB also led to a greater improvement in lipoprotein parameters that confer an atherogenic profile. Therefore, the presence of elevated levels of LDL cholesterol should be considered when determining the optimal bariatric surgery procedure for each patient.Trial registrationClinicaltrials.gov number, NCT03975478).Graphical abstract

Identification and Characterization of the Lipoprotein N-acyltransferase in Bacteroides.

Members of the Bacteroidota compose a large portion of the human gut microbiota, contributing to overall gut health via the degradation of various polysaccharides. This process is facilitated by lipoproteins, globular proteins anchored to the cell surface by a lipidated N-terminal cysteine. Despite their importance, lipoprotein synthesis by these bacteria is understudied. In E. coli, the α-amino linked lipid of lipoproteins is added by the lipoprotein N-acyltransferase Lnt. Herein, we have identified a protein distinct from Lnt responsible for the same process in Bacteroides, named lipoprotein N-acyltransferase in Bacteroides (Lnb). Deletion of Lnb yields cells that synthesize diacylated lipoproteins, with impacts on cell viability and morphology, growth on polysaccharides, and protein composition of membranes and outer membrane vesicles (OMVs). Our results not only challenge the accepted paradigms of lipoprotein biosynthesis in Gram-negative bacteria, but also support the establishment of a new family of lipoprotein N-acyltransferases.

Raman-AFM-fluorescence-guided impact of linoleic and eicosapentaenoic acids on subcellular structure and chemical composition of normal and cancer human colon cells

The regular overconsumption of high-energy food (rich in lipids and sugars) results in elevated nutrient absorption in intestine and consequently excessive accumulation of lipids in many organs e.g.: liver, adipose tissue, muscles. In the long term this can lead to obesity and obesity-associated diseases e.g. type 2 diabetes, non-alcoholic fatty liver disease, cardiovascular disease, inflammatory bowel disease (IBD). In the presented paper based on RI data we have proved that Raman maps can be used successfully for subcellular structures visualization and analysis of fatty acids impact on morphology and chemical composition of human colon single cells – normal and cancer. Based on Raman data we have investigated the changes related to endoplasmic reticulum, mitochondria, lipid droplets and nucleus. Analysis of ratios calculated based on Raman bands typical for proteins (1256, 1656 cm−1), lipids (1304, 1444 cm−1) and nucleic acids (750 cm−1) has confirmed for endoplasmic reticulum the increased activity of this organelle in lipoproteins synthesis upon FAs supplementation; for LDs the changes of desaturation of accumulated lipids with the highest unsaturation level for CaCo-2 cells upon EPA supplementation; for mitochondria the stronger effect of FAs supplementation was observed for CaCo-2 cells confirming the increased activity of this organelle responsible for energy production necessary for tumor development; the weakest impact of FAs supplementation was observed for nucleus for both types of cells and both types of acids. Fluorescence imaging was used for the investigations of changes in LDs/ER morphology. Our measurements have shown the increased area of LDs/ER for CaCo-2 cancer cells, and the strongest effect was noticed for CaCo-2 cells upon EPA supplementation. The increased participation of lipid structures for all types of cells upon FAs supplementation has been confirmed also by AFM studies. The lowest YM values have been observed for CaCo-2 cells including samples treated with FAs.

Integrated meta-omics reveals the regulatory landscape involved in lipid metabolism between pig breeds

BackgroundDomesticated pigs serve as an ideal animal model for biomedical research and also provide the majority of meat for human consumption in China. Porcine intramuscular fat content associates with human health and diseases and is essential in pork quality. The molecular mechanisms controlling lipid metabolism and intramuscular fat accretion across tissues in pigs, and how these changes in response to pig breeds, remain largely unknown.ResultsWe surveyed the tissue-resident cell types of the porcine jejunum, colon, liver, and longissimus dorsi muscle between Lantang and Landrace breeds by single-cell RNA sequencing. Combining lipidomics and metagenomics approaches, we also characterized gene signatures and determined key discriminating markers of lipid digestibility, absorption, conversion, and deposition across tissues in two pig breeds. In Landrace, lean-meat swine mainly exhibited breed-specific advantages in lipid absorption and oxidation for energy supply in small and large intestinal epitheliums, nascent high-density lipoprotein synthesis for reverse cholesterol transport in enterocytes and hepatocytes, bile acid formation, and secretion for fat emulsification in hepatocytes, as well as intestinal-microbiota gene expression involved in lipid accumulation product. In Lantang, obese-meat swine showed a higher synthesis capacity of chylomicrons responsible for high serum triacylglycerol levels in small intestinal epitheliums, the predominant characteristics of lipid absorption in muscle tissue, and greater intramuscular adipcytogenesis potentials from muscular fibro-adipogenic progenitor subpopulation.ConclusionsThe findings enhanced our understanding of the cellular biology of lipid metabolism and opened new avenues to improve animal production and human diseases.D7xkEMpXE5aNHjWuhXhcDpVideo

Comparative characterization of liver morphometric parameters during pregnancy in experimental chronic renal failure

Study of morphological and morphometric changes of the liver of pregnant white rats after chronic renal failure. [9]. A study of normal morphological and morphometric parameters of the liver of pregnant white rats. Study of the anatomical parameters of the liver of purebred rats in pregnancy and its reactive changes after experimental chronic renal failure Comparison of pregnancy-related histo-topographic features of the liver of purebred rats in experimental chronic renal failure with parameters of healthy rats; [10]. Comparative classification of morphometric changes in the liver of pregnant rats after correction with Juyzar waters in experimental chronic renal failure.Glomerulopathies: focal glomerulosclerosis, membranous and membranous-proliferative glomerulonephritis, the damage of kidney balls is reduced in the primary order. Due to the alteration of the basal membrane of the glomerulus, increased permeability leads to proteinuria. [17]. Prolonged proteinuria results in decreased albumin in the blood plasma (Hypoalbuminemia). The quality of albumin and globulin changes. A decrease in albumin leads to a decrease in osmotic pressure. The passage of fluid from the blood to the tissue increases. The function of sodium and potassium pumps is disturbed. Swelling develops. At the same time, the reduction of albumin leads to an increase in the synthesis of lipoproteins. [16]. This has an effect on the oncotic pressure. The release of a large amount of lipids in the urine is a sign that the permeability of the glomerular basement membrane has changed.

Lipophorin: The Lipid Shuttle.

Insects need to transport lipids through the aqueous medium of the hemolymph to the organs in demand, after they are absorbed by the intestine or mobilized from the lipid-producing organs. Lipophorin is a lipoprotein present in insect hemolymph, and is responsible for this function. A single gene encodes an apolipoprotein that is cleaved to generate apolipophorin I and II. These are the essential protein constituents of lipophorin. In some physiological conditions, a third apolipoprotein of different origin may be present. In most insects, lipophorin transports mainly diacylglycerol and hydrocarbons, in addition to phospholipids. The fat body synthesizes and secretes lipophorin into the hemolymph, and several signals, such as nutritional, endocrine, or external agents, can regulate this process. However, the main characteristic of lipophorin is the fact that it acts as a reusable shuttle, distributing lipids between organs without being endocytosed or degraded in this process. Lipophorin interacts with tissues through specific receptors of the LDL receptor superfamily, although more recent results have shown that other proteins may also be involved. In this chapter, we describe the lipophorin structure in terms of proteins and lipids, in addition to reviewing what is known about lipoprotein synthesis and regulation. In addition, we reviewed the results investigating lipophorin's function in the movement of lipids between organs and the function of lipophorin receptors in this process.

Transfer Proteins, Lipoprotein Remodeling, and Antioxidant Action on Pregnant Women: Comparison from the First to the Third Trimester of Gestation

Introduction: During pregnancy, maternal lipid metabolism undergoes several transformations originated by hormonal changes. There are two distinct phases: initial and late, finally driven to hypertriglyceridemia. Maternal hyperlipidemia, especially hypertriglyceridemia, is associated with an increased hepatic very-low-density lipoprotein (VLDL) synthesis stimulated by high estrogen levels during gestation. Objectives: This study aimed to evaluate the action of possible lipoproteins remodeling modulators, such as phospholipid and cholesteryl-ester transfer proteins (PLTP and CETP), paraoxonase-1 (PON-1), and apolipoproteins (apo), during gestation. Methods: An observational prospective cohort study composed of 40 pregnant women was conducted. Blood samples were collected in two moments: at the first and third trimesters of gestation, followed by the biochemical determination of apo A-I, apo B, lipid profile, PON-1, PLTP and CETP activities, and HDL particle size. Results: The majority of pregnant women in the third trimester showed dyslipidemia, mainly hypertriglyceridemia. In the third trimester of gestation, we observed an increase in CETP activity (70.5 ± 9.6 pmol/µL/h; p &lt;0.001) and TG/HDL-C ratio (2.7 [2.0-3.8]), but on the other hand, PON-1 activity (65.4 [46.5-105] nMol of p-nitrophenol/min/mL) decreased. High-density level lipoprotein (HDL) particle size and PLTP activity did not differ in the two studied moments. The serum triglyceride concentration and CETP activity showed a positive linear correlation in the first trimester of gestation (r2=0.65, p&lt;0.001). Conclusion: Data suggest that the CETP activity, antioxidant profile, and low-density lipoprotein (LDL) remodeling are modified by physiological metabolic changes during an uncomplicated gestational period.

Essential role of Helicobacter pylori apolipoprotein N-acyltransferase (Lnt) in stomach colonization.

Bacterial lipoproteins are post-translationally modified with acyl chains, anchoring these proteins to bacterial membranes. In Gram-negative bacteria, three enzymes complete the modifications. Lgt (which adds two acyl chains) and LspA (which removes the signal peptide) are essential. Lnt (which adds a third acyl chain) is not essential in certain bacteria including Francisella tularensis, Neisseria gonorrhoeae, and Acinetobacter baumannii. Deleting lnt results in mild to severe physiologic changes. We previously showed lnt is not essential for Helicobacter pylori growth in vitro. Here, the physiologic consequences of deleting lnt in H. pylori and the role of Lnt in the host response to H. pylori were examined using in vitro and in vivo models. Comparing wild-type, Δlnt, and complemented mutant H. pylori, no changes in growth rates or sensitivity to acid or antibiotics were observed. Since deleting lnt changes the number of acyl chains on lipoproteins and the number of acyl chains on lipoproteins impacts the innate immune response through Toll-like receptor 2 (TLR2) signaling, primary human gastric epithelial cells were treated with a purified lipoprotein from wild-type or lnt mutant H. pylori. Differential gene expression analysis indicated that lipoprotein from the lnt mutant induced a more robust TLR2 response. In a complementary approach, we infected wild-type and Tlr2-/- mice and found that both the wild-type and complemented mutant strains successfully colonized the animals. However, the lnt mutant strain was unable to colonize either mouse strain. These results show that lnt is essential for H. pylori colonization and identifies lipoprotein synthesis as a target for therapeutic intervention.

α-Tocopherol reduces VLDL secretion through modulation of intracellular ER-to-Golgi transport of VLDL.

Avoiding hepatic steatosis is crucial for preventing liver dysfunction, and one mechanism by which this is accomplished is through synchronization of the rate of very low density lipoprotein (VLDL) synthesis with its secretion. Endoplasmic reticulum (ER)-to-Golgi transport of nascent VLDL is the rate-limiting step in its secretion and is mediated by the VLDL transport vesicle (VTV). Recent in vivo studies have indicated that α-tocopherol (α-T) supplementation can reverse steatosis in nonalcoholic fatty liver disease, but its effects on hepatic lipoprotein metabolism are poorly understood. Here, we investigated the impact of α-T on hepatic VLDL synthesis, secretion, and intracellular ER-to-Golgi VLDL trafficking using an in vitro model. Pulse-chase assays using [3H]-oleic acid and 100 µmol/L α-T demonstrated a disruption of early VLDL synthesis, resulting in enhanced apolipoprotein B-100 expression, decreased expression in markers for VTV budding, ER-to-Golgi VLDL transport, and reduced VLDL secretion. Additionally, an in vitro VTV budding assay indicated a significant decrease in VTV production and VTV-Golgi fusion. Confocal imaging of lipid droplet (LD) localization revealed a decrease in overall LD retention, diminished presence of ER-associated LDs, and an increase in Golgi-level LD retention. We conclude that α-T disrupts ER-to-Golgi VLDL transport by modulating the expression of specific proteins and thus reduces VLDL secretion.

Butyrylcholinesterase and lipid metabolism: Possible dual role in metabolic disorders

Butyrylcholinesterase (BChE), an enzyme primarily found in the liver, plasma, and brain, has been recognized for its role in the hydrolysis of choline esters. Recent studies have shed light on its involvement in lipid metabolism, revealing its potential as a crucial player in maintaining lipid homeostasis. However, the interactions between external factors and BChE activity in lipid metabolic pathways remain a complex subject of study. This review summarizes the current knowledge regarding BChE activity and lipid metabolism and seeks to clarify the nature of this relationship as causal or consequential. Evidence supports the role of BChE in energy homeostasis disruption, such as obesity and related metabolic disorders, where it exhibits lipolytic activity and mediates fatty acid use and storage. The unexpected functions of BChE in lipoprotein synthesis and the impact of polymorphic variants of the BCHE gene suggest a central role in lipid metabolism; however, further investigation is needed to confirm and describe these functions, especially considering the metabolic context. Furthermore, exploring therapeutic interventions in lipid metabolism disorders contributes to elucidating their implications on BChE activity, but attention to the metabolic status and genotypes as possible factors in this interaction is needed. In summary, further research in this field holds promise for improving our understanding of the complex interplay between BChE and lipid metabolism, and its potential clinical applications. However, the available data corroborate the dual role of BChE activity, both as a critical responsive element to metabolic challenges and as a predisposition factor to metabolic diseases.

Rumen-protected choline reduces hepatic lipidosis by increasing hepatic triacylglycerol-rich lipoprotein secretion in dairy cows

Objectives were to determine the effects of supplementing rumen-protected choline (RPC) on hepatic composition and secretion of triacylglycerol-rich lipoprotein when cows were subjected to feed restriction to develop fatty liver. It was hypothesized that RPC reduces hepatic triacylglycerol by enhancing secretion of hepatic lipoprotein. Pregnant, nonlactating parous Holstein cows (n = 33) at mean (± standard deviation) 234 ± 2.2 d of gestation were blocked by body condition (3.79 ± 0.49) and assigned to receive 0 g/d (CON), 25.8 g/d choline ion from a RPC product containing 28.8% choline chloride (CC; treatment L25.8), or 25.8 g/d of choline ion from a RPC product containing 60.0% CC (H25.8). Cows were fed for ad libitum intake for the first 5 d and restricted to 41% of the net energy for lactation required for maintenance and pregnancy from d 6 to 13. Intake of metabolizable methionine was maintained at 18 g/d during feed restriction by supplying rumen-protected methionine. Hepatic tissue was sampled on d 6 and 13 and analyzed for triacylglycerol and glycogen, and mRNA expression of hepatic tissue was investigated. On d 14, cows were not fed and received a 10% solution of tyloxapol intravenously at 120 mg/kg of body weight to block hydrolysis of triacylglycerols in very low density lipoprotein (VLDL). Blood was sampled sequentially for 720 min and analyzed for concentration of triacylglycerol and total cholesterol. Lymph was sampled 6 h after tyloxapol infusion, and analyzed for concentrations of fatty acids, β-hydroxybutyrate, glucose, triacylglycerol, and total cholesterol. A sample of serum collected at 720 min after tyloxapol was assayed for the metabolome composition. The area under the curve (AUC) of serum triacylglycerol, VLDL cholesterol, and total cholesterol were calculated. Orthogonal contrasts evaluated the effect of supplementing RPC (CON vs. [1/2 L25.8 + 1/2 H25.8]) and source of RPC (L25.8 vs. H25.8). Least squares means and standard errors of the means are presented in sequence as CON, L25.8, H25.8. During feed restriction, supplementation of RPC reduced hepatic triacylglycerol (9.0 vs. 4.1 vs. 4.5 ± 0.6%) and increased glycogen contents (1.9 vs. 3.5 vs. 4.1 ± 0.2%). Similarly, supplementation of RPC increased the expression of transcripts involved in the synthesis and assembly of lipoproteins (MTTP), cellular autophagy (ATG3), and inflammation (TNFA), and reduced the expression of transcripts associated with mitochondrial oxidation of fatty acids (HADHA, MLYCD) and stabilization of lipid droplets (PLIN2). After infusion of tyloxapol, RPC increased the AUC for serum triacylglycerol (21,741 vs. 32,323 vs. 28,699 ± 3,706 mg/dL × min) and VLDL cholesterol (4,348 vs. 6,465 vs. 5,740 ± 741 mg/dL × min) but tended to reduce the concentrations of triacylglycerol in lymph (16.7 vs. 13.8 vs. 11.9 ± 1.9 mg/dL). Feeding RPC tended to increase the concentrations of 89 metabolites in serum, after adjusting for false discovery, including 3 acylcarnitines, 1 AA-related metabolite, 11 bile acids, 1 ceramide, 6 diacylglycerols, 2 dihydroceramides, 1 glycerophospholipid, and 64 triacylglycerols compared with CON. Feeding 25.8 g/d of choline ion as RPC mediated increased hepatic triacylglycerol secretion to promote lipotropic effects that reduced hepatic lipidosis in dairy cows.

Effect of source and amount of rumen-protected choline on hepatic metabolism during induction of fatty liver in dairy cows

Objectives were to determine the effect of supplementing increased amounts of rumen-protected choline (RPC) from sources with low (L, 28.8%) or high (H, 60.0%) concentration of choline chloride on hepatic metabolism when cows were subjected to feed restriction to develop fatty liver. It was hypothesized that increased supplementation of RPC reduces hepatic triacylglycerol and enhances glycogen concentrations. Pregnant, nonlactating multiparous Holstein cows (n = 110) at mean (± standard deviation) 232 ± 3.9 d of gestation were blocked by body condition (4.01 ± 0.52) and assigned to receive 0 (CON), 12.9 (L12.9 or H12.9), or 25.8 (L25.8 or H25.8) g/d of choline ion. Cows were fed for ad libitum intake on d 1 to 5 and restricted to 50% of the NEL required for maintenance and pregnancy from d 6 to 13. Intake of metabolizable methionine was maintained at 19 g/d during the feed restriction period by supplying rumen-protected methionine. Hepatic tissue was sampled on d 6 and 13 and analyzed for triacylglycerol, glycogen, and mRNA expression of genes involved in choline, glucose, and fatty acids metabolism, cell signaling, inflammation, autophagy, lipid droplet dynamics, lipophagy, and endoplasmic reticulum stress response. Blood was sampled and analyzed for concentrations of fatty acids, β-hydroxybutyrate (BHB), glucose, triacylglycerol, total cholesterol, and haptoglobin. Orthogonal contrasts evaluated the effect of supplementing RPC [CON vs. (1/4·L12.9 + 1/4·L25.8 + 1/4·H12.9 + 1/4·H25.8)], source of RPC [(1/2·L12.9 + 1/2·L25.8) vs. (1/2·H12.9 + 1/2·H25.8)], amount of RPC [(1/2·L12.9 + 1/2·H12.9) vs. (1/2·L25.8 + 1/2·H25.8)], and interaction between source and amount [(1/2·L12.9 + 1/2·H25.8) vs. (1/2·H12.9 + 1/2·L25.8)]. Least squares means and standard error of the means are presented in sequence as CON, L12.9, L25.8, H12.9, H25.8. Supplementation of RPC reduced hepatic triacylglycerol (9.3 vs. 6.6 vs. 5.1 vs. 6.6 vs. 6.0 ± 0.6% as-is) and increased glycogen contents (1.8 vs. 2.6 vs. 3.6 vs. 3.1 vs. 4.1 ± 0.2% as-is) on d 13 of the experiment. Feeding RPC reduced serum haptoglobin (136.6 vs. 85.6 vs. 80.6 vs. 82.8 vs. 81.2 ± 4.6 µg/mL) during the feed restriction period; however, blood concentrations of fatty acids, BHB, glucose, triacylglycerol, and total cholesterol did not differ among treatments. During feed restriction, supplementation of RPC enhanced the mRNA expression of genes related to choline metabolism (BHMT), uptake of fatty acids (CD36), and autophagy (ATG3), and reduced the expression of a transcript associated with endoplasmic reticulum stress response (ERN1). An increase in the amount of choline ion from 12.9 to 25.8 g/d enhanced the mRNA expression of genes associated with synthesis and assembly of lipoproteins (APOB100), and inflammation (TNFA), whereas it reduced the expression of genes linked to gluconeogenesis (PC), oxidation of fatty acids (ACADM, MMUT), ketogenesis (ACAT1), and synthesis of antioxidants (SOD1) on d 13 of the experiment. Feeding RPC, independent of the product used, promoted lipotropic effects that reduced hepatic lipidosis in dairy cows.

Nephrotic syndrome presented as a portal vein thrombosis: a case report.

In the presenting case report, we described a 21-year-old woman with no history of NS and a hypercoagulable state who presented to our emergency department with severe generalized abdominal pain and lower limb edema. She was subsequently diagnosed with NS complicated with portal vein thrombosis and was admitted to our internal medicine unit. After 2 weeks of treatment, the patient was discharged in good health. Additional evaluation for newly onset NS with venous thrombosis should be needed in the presence of severe abdominal pain and lower limb edema even in a patient without a previous history of NS.

Study of serum lipid profile in patients with chronic liver disease and its correlation with child Pugh class: a hospital based observational study in North Indian patients

Background: Liver disease impacts on hepatic synthesis of lipoproteins and lipogenesis but data on dyslipidemia during disease progression are limited. We want assess the patterns of dyslipidemia in with different etiology liver disease and its correlation with Child Pugh score from non-advanced (non-ACLD) advanced chronic liver disease (ACLD) as it is unclear how progression to ACLD impacts on dyslipidemia-associated cardiovascular risk. Aim and objectives of current study were to determine serum lipid profile in patients with chronic liver disease and its correlation with Child Pugh score. Methods: It was Cross sectional, observational study conducted in 200 patients at KPS post graduate institute of medicine, GSVM medical college, Kanpur from December 2020 to October 2022. Results: In this study mean value of Serum Cholesterol (mg/dl) was 135.25 (27.88), Serum Triglycerides (mg/dl) was 122.27 (36.29), HDL Cholesterol was 46.92 (10.36), LDL Cholesterol was 62.77 (22.59), VLDL Cholesterol was 25.62 (8.71). In this study maximum patients of chronic liver disease were due to chronic alcohol intake which account for 76% patients, 2nd most common aetiology of chronic liver disease were chronic viral hepatitis and rest were due to Wilson disease, Budd Chiari syndrome non cirrhotic portal fibrosis and cryptogenic. Patients of chronic liver disease have negative correlation on lipid profile with Child Pugh score. Conclusions: From our study its was concluded that patients having higher CTP score having more derangement (low) in serum lipid profile (specially) serum cholesterol, serum HDL, serum VLDL) than the patients having low CTP score.

Effect of High Fat and Cholesterol Diet on Total Blood Cholesterol Levels in Pregnant Wistar Rats

Hypercholesterolemia during pregnancy is a physiological condition resulting from increased insulin resistance, lipoprotein synthesis, and lipolysis in adipose tissue, which mobilizes lipids as an energetic substrate for fetal growth. Consumption of foods high in fat and cholesterol may lead to an increase in total blood cholesterol levels during pregnancy due to saturated fat and cholesterol contents that will increases the synthesis of lipoproteins in the blood. The objectives of this study were to determine the effects of high fat and cholesterol diet on the total blood cholesterol levels in pregnant Wistar rats. This study was a true experimental research using a randomized post-test-only control group design conducted from November 2020 to October 2021on fourteen female Wistar rats that were divided into control and intervention groups. Cow brain was provided as the high fat and cholesterol diet and after the rats gave birth, blood was drawn from the heart. The total blood serum cholesterol levels were assessed using Micro Lab 300 with the CHOD-PAP method and the data were analyzed using an independent t-test. This study showed that the mean total blood cholesterol levels for the control and treatment groups were 80.43±18.512 mg/dL and 142.57±24.786 mg/dL, respectively, which reflected a significant differences in the mean total blood cholesterol level between the control and treatment groups (p-value &lt;0.01). In conclusion, a high fat and cholesterol diet affects the total blood cholesterol level in pregnant Wistar rats.

Identification of an Essential LolD-Like Protein in Helicobacter pylori.

The localization of lipoprotein (Lol) system is used by Gram-negative bacteria to export lipoproteins to the outer membrane. Lol proteins and models of how Lol transfers lipoproteins from the inner to the outer membrane have been extensively characterized in the model organism Escherichia coli, but in numerous bacterial species, lipoprotein synthesis and export pathways deviate from the E. coli paradigm. For example, in the human gastric bacterium Helicobacter pylori, a homolog of the E. coli outer membrane component LolB is not found, E. coli LolC and LolE correspond to a single inner membrane component (LolF), and a homolog of the E. coli cytoplasmic ATPase LolD has not been identified. In the present study, we sought to identify a LolD-like protein in H. pylori. We used affinity-purification mass spectrometry to identify interaction partners of the H. pylori ATP-binding cassette (ABC) family permease LolF and identified the ABC family ATP-binding protein HP0179 as its interaction partner. We engineered H. pylori to conditionally express HP0179 and showed that HP0179 and its conserved ATP binding and ATP hydrolysis motifs are essential for H. pylori growth. We then performed affinity purification-mass spectrometry using HP0179 as the bait and identified LolF as its interaction partner. These results indicate that H. pylori HP0179 is a LolD-like protein and provide a more complete understanding of lipoprotein localization processes in H. pylori, a bacterium in which the Lol system deviates from the E. coli paradigm. IMPORTANCE Lipoproteins are critical in Gram-negative-bacteria for cell surface assembly of LPS, insertion of outer membrane proteins, and sensing envelope stress. Lipoproteins also contribute to bacterial pathogenesis. For many of these functions, lipoproteins must localize to the Gram-negative outer membrane. Transporting lipoproteins to the outer membrane involves the Lol sorting pathway. Detailed analyses of the Lol pathway have been performed in the model organism Escherichia coli, but many bacteria utilize altered components or are missing essential components of the E. coli Lol pathway. Identifying a LolD-like protein in Helicobacter pylori is important to better understand the Lol pathway in diverse bacterial classes. This becomes particularly relevant as lipoprotein localization is targeted for antimicrobial development.

Injection of an improperly stored proprotein convertase subtilisin/kexin type 9 monoclonal antibody in a patient with secondary dyslipidemia from nephrotic syndrome: a case report

BackgroundElevated plasma cholesterol and/or plasma triglyceride levels in nephrotic syndrome patients are the result of impaired lipoprotein clearance and a compensatory increase in hepatic lipoprotein synthesis. Plasma proprotein convertase subtilisin/kexin type 9 levels directly correlate to the amount of proteinuria in nephrotic syndrome patients. Proprotein convertase subtilisin/kexin type 9 monoclonal antibody has been used to treat dyslipidemia in some refractory nephrotic syndrome cases. As a therapeutic protein, proprotein convertase subtilisin/kexin type 9 monoclonal antibody simply deteriorates if stored in inappropriate temperatures or conditions.Case presentationIn this article, we present the case of a 16-year-old Thai female with severe combined dyslipidemia secondary to refractory nephrotic syndrome. She received proprotein convertase subtilisin/kexin type 9 monoclonal antibody (alirocumab) treatment. However, the drugs were mistakenly frozen in a freezer for up to 17 hours before being stored at 4 °C. After using two frozen devices, serum total cholesterol, free proprotein convertase subtilisin/kexin type 9, and lipoprotein(a) significantly decreased. Nonetheless, the patient developed a skin rash 2 weeks after the second injection and the lesion spontaneously resolved without any treatment approximately 1 month later.ConclusionsThe effectiveness of proprotein convertase subtilisin/kexin type 9 monoclonal antibody seems to be stable after being stored under freeze–thaw conditions. However, improperly stored drugs should be discarded to avoid any potential undesirable side effects.

Deciphering the role of lipoproteins and lipid metabolic alterations in ageing and ageing-associated renal fibrosis.

Fibrosis is the ultimate pathological feature of many chronic diseases, and ageing a major risk factor for fibrotic diseases. Current therapies are limited to those that reduce the rate of functional decline in patients with mild to moderate disease, but few interventions are available to specifically target the pathogenesis of fibrosis. In this context, new treatments that can significantly improve survival time and quality of life for these patients are urgently needed. In this review, we outline both the synthesis and metabolism of lipids and lipoproteins associated with ageing-associated renal fibrosis and the prominent contribution of lipids and lipidomics in the discovery of biomarkers that can be used for the prevention, diagnosis, and treatment of renal ageing and fibrosis. Next, we describe the effect of dyslipidaemia on ageing-related renal fibrosis and the pathophysiological changes in the kidney caused by dyslipidaemia. We then summarize the enzymes, transporters, transcription factors, and RNAs that contribute to dysregulated lipid metabolism in renal fibrosis and discuss their role in renal fibrosis in detail. We conclude by discussing the progress in research on small molecule therapeutic agents that prevent and treat ageing and ageing-associated renal fibrosis by modulating lipid metabolism. A growing number of studies suggest that restoring aberrant lipid metabolism may be a novel and promising therapeutic strategy to combat ageing and ageing-associated renal fibrosis.

Interactions between structure and function of resistant glucans for alleviating type 2 diabetes mellitus (T2DM) and its complications in mice

Resistant glucan, a functional dietary fiber, has been shown to alleviate type 2 diabetes mellitus (T2DM) and its complications in clinical studies. However, the interactions between the special structure of resistant glucan and the metabolism-related pathways in T2DM have not yet been systematically studied. This study identified the structural differences between resistant glucans prepared by new and old methods. Oral gavage with two resistant glucans in T2DM mice, led to significant improvements in glucose and lipid metabolism as measured by related indicators (including gut microbiota, fecal metabolites, and physiological and biochemical indexes). According to these results, in addition to van der Waals forces, micelle formation, and hydrogen bonding, the branching structures of resistant glucans produced more hydroxyl, carbonyl, and keto groups that linked cholesterols, cholesterol esters, and low-density lipoprotein intermediates. Moreover, after lipid clearing, the metabolic environment was more conducive to the proliferation of specific gut microbiota (including Phascolarctobacterium, Prevotella, Butyricicoccus, Weissella, and Anaerostipes) with decreasing abundance ratios of Firmicutes and Bacteroides. This facilitated the synthesis of high-density lipoprotein, conversion of cholesterol into coprostanol, and production of short-chain fatty acids and bile acids. Our findings provide a foundation for comprehensive investigation of the structure of resistant glucan in the promotion and prevention of T2DM.