Multifunctional glycolipids as multi-targeting therapeutics for neural regeneration

Many patients with neurodegenerative diseases,such as Alzheimer’s(AD)and Parkinson’s(PD)diseases suffer from disease progression without any satisfying clinical intervention,likely due to our lack of knowledge on how normal aging impacts the pathogenic mechanisms of these debilitating diseases.A growing body of literature has emerged in recent years that clearly demonstrates the involvement of glycolipids in the protein-oligomerization of neurodegenerative disorders.We hypothesize that changes in glycolipids composition are a common mechanism underlying the shift from healthy brain aging to the neuropathological processes of neurodegenerative diseases.

Effects of Radix Puerariae, Radix Rehmanniae and Their Compatibility on Blood Glucose and Blood Lipids in Mice

[Objectives]To explore the effects of the compatibility of Radix Puerariae and Radix Rehmanniae on blood glucose and blood lipids in diabetic mouses.[Methods]Diabetic mouse model was established.The body weight and fasting blood glucose of mice were measured after 7 and 14 d of administration,and the biochemical indicators of blood lipids(TC,HDL-C,and LDL-C)were detected after 14 d of administration.[Results]Compared with the Radix Puerariae group and Radix Rehmanniae group,the compatibility group(1:2)had the best hypoglycemic effect(P<0.05),and TC and LDL-C in the compatibility group(2:1)significantly decreased(P<0.05),while HDL-C in the compatibility group(1:1)significantly increased(P<0.05).[Conclusions]Radix Puerariae,Radix Rehmanniae and their combination can reduce the blood glucose of diabetic mice.The compatibility group(1:2)had a significant hypoglycemic effect(P<0.05),and LDL-C in the compatibility group(2:1)significantly declined,while HDL-C in the compatibility group(1:1)rose significantly.

Lipids,lipid-lowering drug and sepsis:a Mendelian randomization study

lipid-lowering interventions on the disease.Methods:Two-sample Mendelian randomization analyses were conducted to evaluate the associations of high-density lipoprotein cholesterol,low-density lipoprotein cholesterol,triglycerides,apolipoprotein B and apolipoprotein A-I levels with risks for sepsis,and those of low-density lipoprotein cholesterol(HMGCR,PCSK9,NPC1L1),triglycerides(LPL,ANGPTL3,APOC3)and high-density lipoprotein cholesterol(CETP),apolipoprotein A-I(CETP),apolipoprotein B(HMGCR,PCSK9,NPC1L1,LPL,APOC3)with sepsis.Results:HMGCR-mediated low-density lipoprotein cholesterol and apolipoprotein B were associated with an increased risk of sepsis,with an odds ratio value of 1.4(95%confidence interval(CI):1.06-1.84,P=0.017)and 1.41(95%CI:1.01-1.98,P=0.046).CETP-mediated high-density lipoprotein cholesterol and apolipoprotein A-I were associated with a reduced risk of sepsis,with an odds ratio of 0.87(95%CI:0.82-0.92,P<0.01)respectively and 0.84(95%CI:0.78-0.9,P<0.01).Sensitivity analysis showed that the results were robust.Conclusion:HMG-CoA reductase inhibitors and CETP inhibitors may contribute to the prevention and treatment of sepsis.

Chronic Supplementation with L-Isoleucine Alone or in Combination with Exercise Reduces Hepatic Cholesterol Levels with No Effect on Serum Glucose, Insulin, or Lipids in Rats Fed a High Fructose Diet

The thought of using branched-chain amino acids (BCAA) in the prevention and treatment of certain disorders is becoming increasingly popular. Individual BCAA use has been associated with improving glucose tolerance and liver disease. Previous studies have cited improvements in glucose metabolism with a single dose of L-isoleucine (ILE). However, it is still unclear whether chronic consumption of ILE has any direct benefit. The objective of this study was to examine the influence of chronic ILE supplementation alone or in combination with exercise on fasting serum glucose, insulin, lipids, and lipoprotein cholesterol levels;glucose tolerance;and hepatic lipids in rats. Male Sprague-Dawley rats (n = 40) were divided into Control (low fructose diet);High Fructose diet (HF);HF plus 1.5% ILE (HF + ILE);HF plus exercise (HF + EX);and HF plus 1.5% ILE and exercise (HF + ILE + EX). The HF diets consisted of 70% kcalories from fructose. After 6 weeks of treatment, no significant differences were observed between groups for changes in fasting serum glucose, insulin, lipids, or lipoprotein cholesterol levels. However, hepatic total cholesterol was significantly lower in the HF + ILE + EX compared to the Control and HF, while, the HF + ILE had significantly lower hepatic free cholesterol compared to the HF. We also found no differences between groups for serum glucose response following an oral glucose tolerance test. In conclusion, our study shows that ILE supplementation in rats does not influence serum glucose and lipid biomarkers but may have an influence on lipid metabolic pathways within the liver.

Astrocytic endothelin-1 overexpression impairs learning and memory ability in ischemic stroke via altered hippocampal neurogenesis and lipid metabolism

Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However,the way in which changes in astrocytic endothelin-1 lead to poststroke cognitive deficits following transient middle cerebral artery occlusion is not well understood.Here,using mice in which astrocytic endothelin-1 was overexpressed,we found that the selective overexpression of endothelin-1 by astrocytic cells led to ischemic stroke-related dementia(1 hour of ischemia;7 days,28 days,or 3 months of reperfusion).We also revealed that astrocytic endothelin-1 overexpression contributed to the role of neural stem cell proliferation but impaired neurogenesis in the dentate gyrus of the hippocampus after middle cerebral artery occlusion.Comprehensive proteome profiles and western blot analysis confirmed that levels of glial fibrillary acidic protein and peroxiredoxin 6,which were differentially expressed in the brain,were significantly increased in mice with astrocytic endothelin-1 overexpression in comparison with wild-type mice 28 days after ischemic stroke.Moreover,the levels of the enriched differentially expressed proteins were closely related to lipid metabolism,as indicated by Kyoto Encyclopedia of Genes and Genomes pathway analysis.Liquid chromatography-mass spectrometry nontargeted metabolite profiling of brain tissues showed that astrocytic endothelin-1 overexpression altered lipid metabolism products such as glycerol phosphatidylcholine,sphingomyelin,and phosphatidic acid.Overall,this study demonstrates that astrocytic endothelin-1 overexpression can impair hippocampal neurogenesis and that it is correlated with lipid metabolism in poststroke cognitive dysfunction.

Lipid metabolism analysis in esophageal cancer and associated drug discovery

Esophageal cancer is an upper gastrointestinal malignancy with a bleak prognosis.It is still being explored in depth due to its complex molecular mechanisms of occurrence and development.Lipids play a crucial role in cells by participating in energy supply,biofilm formation,and signal transduction processes,and lipid metabolic reprogramming also constitutes a significant characteristic of malignant tumors.More and more studies have found esophageal cancer has obvious lipid metabolism abnormalities throughout its beginning,progress,and treatment resistance.The inhibition of tumor growth and the enhancement of antitumor therapy efficacy can be achieved through the regulation of lipid metabolism.Therefore,we reviewed and analyzed the research results and latest findings for lipid metabolism and associated analysis techniques in esophageal cancer,and comprehensively proved the value of lipid metabolic reprogramming in the evolution and treatment resistance of esophageal cancer,as well as its significance in exploring potential therapeutic targets and biomarkers.

Dietary sodium acetate and sodium butyrate improve high-carbohydrate diet utilization by regulating gut microbiota, liver lipid metabolism, oxidative stress, and inflammation in largemouth bass(Micropterus salmoides)

Background Adequate level of carbohydrates in aquafeeds help to conserve protein and reduce cost. However, studies have indicated that high-carbohydrate(HC) diet disrupt the homeostasis of the gut–liver axis in largemouth bass, resulting in decreased intestinal acetate and butyrate level.Method Herein, we had concepted a set of feeding experiment to assess the effects of dietary sodium acetate(SA) and sodium butyrate(SB) on liver health and the intestinal microbiota in largemouth bass fed an HC diet. The experimental design comprised 5 isonitrogenous and isolipidic diets, including LC(9% starch), HC(18% starch), HCSA(18% starch;2 g/kg SA), HCSB(18% starch;2 g/kg SB), and HCSASB(18% starch;1 g/kg SA + 1 g/kg SB). Juvenile largemouth bass with an initial body weight of 7.00 ± 0.20 g were fed on these diets for 56 d.Results We found that dietary SA and SB reduced hepatic triglyceride accumulation by activating autophagy(ATG101, LC3B and TFEB), promoting lipolysis(CPT1α, HSL and AMPKα), and inhibiting adipogenesis(FAS, ACCA, SCD1 and PPARγ). In addition, SA and SB decreased oxidative stress in the liver(CAT, GPX1α and SOD1) by activating the Keap1-Nrf2 pathway. Meanwhile, SA and SB alleviated HC-induced inflammation by downregulating the expression of pro-inflammatory factors(IL-1β, COX2 and Hepcidin1) through the NF-κB pathway. Importantly, SA and SB increased the abundance of bacteria that produced acetic acid and butyrate(Clostridium_sensu_stricto_1). Combined with the KEGG analysis, the results showed that SA and SB enriched carbohydrate metabolism and amino acid metabolism pathways, thereby improving the utilization of carbohydrates. Pearson correlation analysis indicated that growth performance was closely related to hepatic lipid deposition, autophagy, antioxidant capacity, inflammation, and intestinal microbial composition.Conclusions In conclusion, dietary SA and SB can reduce hepatic lipid deposition;and alleviate oxidative stress and inflammation in largemouth bass fed on HC diet. These beneficial effects may be due to the altered composition of the gut microbiota caused by SA and SB. The improvement effects of SB were stronger than those associated with SA.

Paclobutrazol induces the concurrent accumulation of chrysolaminarin and lipids in the diatom Phaeodactylum tricornutum

Paclobutrazol is a plant growth regulator and inhibitor of endogenous gibberellin synthesis.It is a powerful inhibitor of vegetative growth by changing the photosynthetic rate and plant hormone levels,thereby affecting plant growth and development.In this study,the effects of paclobutrazol on the model diatom Phaeodactylum tricornutum were investigated.Results show that 2.5-mg/L and 10-mg/L paclobutrazol significantly inhibited the algal growth by inhibiting chlorophyll synthesis,which affects photosynthesis.The antioxidant system,including catalase(CAT)and glutathione peroxidase(GPx)was severely damaged.Chrysolaminarin content was significantly elevated and doubled up to 127 mg/g dry cell weight(DCW)by 10-mg/L paclobutrazol treatment.In combination with transcriptomic analysis,paclobutrazol was demonstrated to play a regulatory role in the accumulation of chrysolaminarin and neutral lipids.

RARRES2 regulates lipid metabolic reprogramming to mediate the development of brain metastasis in triple negative breast cancer

Background Triple negative breast cancer(TNBC),the most aggressive subtype of breast cancer,is characterized by a high incidence of brain metastasis(BrM)and a poor prognosis.As the most lethal form of breast cancer,BrM remains a major clinical challenge due to its rising incidence and lack of effective treatment strategies.Recent evidence suggested a potential role of lipid metabolic reprogramming in breast cancer brain metastasis(BCBrM),but the underlying mechanisms are far from being fully elucidated.Methods Through analysis of BCBrM transcriptome data from mice and patients,and immunohistochemical validation on patient tissues,we identified and verified the specific down-regulation of retinoic acid receptor responder 2(RARRES2),a multifunctional adipokine and chemokine,in BrM of TNBC.We investigated the effect of aberrant RARRES2 expression of BrM in both in vitro and in vivo studies.Key signaling pathway components were evaluated using multi-omics approaches.Lipidomics were performed to elucidate the regulation of lipid metabolic reprogramming of RARRES2.Results We found that downregulation of RARRES2 is specifically associated with BCBrM,and that RARRES2 deficiency promoted BCBrM through lipid metabolic reprogramming.Mechanistically,reduced expression of RARRES2 in brain metastatic potential TNBC cells resulted in increased levels of glycerophospholipid and decreased levels of triacylglycerols by regulating phosphatase and tensin homologue(PTEN)-mammalian target of rapamycin(mTOR)-sterol regulatory element-binding protein 1(SREBP1)signaling pathway to facilitate the survival of breast cancer cells in the unique brain microenvironment.Conclusions Our work uncovers an essential role of RARRES2 in linking lipid metabolic reprogramming and the development of BrM.RARRES2-dependent metabolic functions may serve as potential biomarkers or therapeutic targets for BCBrM.

Hypoxia tolerance in fish depends on catabolic preference between lipids and carbohydrates

Hypoxia is a common environmental stress factor in aquatic organisms,which varies among fish species.However,the mechanisms underlying the ability of fish species to tolerate hypoxia are not well known.Here,we showed that hypoxia response in different fish species was affected by lipid catabolism and preference for lipid or carbohydrate energy sources.Activation of biochemical lipid catabolism through peroxisome proliferator-activated receptor alpha(Pparα)or increasing mitochondrial fat oxidation in tilapia decreased tolerance to acute hypoxia by increasing oxygen consumption and oxidative damage and reducing carbohydrate catabolism as an energy source.Conversely,lipid catabolism inhibition by suppressing entry of lipids into mitochondria in tilapia or individually knocking out three key genes of lipid catabolism in zebrafish increased tolerance to acute hypoxia by decreasing oxygen consumption and oxidative damage and promoting carbohydrate catabolism.However,anaerobic glycolysis suppression eliminated lipid catabolism inhibition-promoted hypoxia tolerance in adipose triglyceride lipase(atgl)mutant zebrafish.Using 14 fish species with different trophic levels and taxonomic status,the fish preferentially using lipids for energy were more intolerant to acute hypoxia than those preferentially using carbohydrates.Our study shows that hypoxia tolerance in fish depends on catabolic preference for lipids or carbohydrates,which can be modified by regulating lipid catabolism.

Effects of Ovariectomy and 17β-Estradiol Replacement on the Activity of Dopamine D2 Receptors in the Selection of Macronutrients Carbohydrates, Lipids and Proteins in Females Rats

17β-estradiol modulates the activity of D2 receptors in the regulation of food intake and body weight. The functional lack of 17β-estradiol in postmenopausal women could create a dietary imbalance and cause body weight gain. This study aimed to better understand the interferences that could exist between 17β-estradiol, D2 receptors and the selection of carbohydrate, fat and protein consumption, as well as their consequences on body weight gain by using an animal model of the menopause. Ovariectomy exacerbates the consumption of foods rich in lipids. Thus confirming an inhibitory action of 17β-estradiol (E2) on the consumption of these types of foods. This consumption stimulates body weight gain, which is promoted by the high caloric content of these foods and not by the amount consumed. Our results showed a direct involvement of D2 receptors in food choice. This choice would be made according to the two (2) isoforms of the D2 receptors. The D2/BR isoform directs towards a high carbohydrate consumption, without causing a gain in body weight. While D2/SUL, promotes high fat food consumption, causing an increase in body weight. In women, 17β-estradiol modulates the activity ratio between these two D2 receptor isoforms to ensure energy and homeostatic balance, stabilizing food intake and body weight.

Altered Levels of Blood Glucose and Serum Lipids in Sudanese Patients with Ovarian Cancer

Background: The etiology of ovarian cancer is not well-understood;numerous metabolomics profiling, epidemiological, and hospital-based case control studies have associated abnormal levels of blood glucose and serum lipids with the risk and the prognosis of various types of cancers including ovarian cancer. The association between the risk of the incidence of ovarian cancer and the alterations in the levels of blood glucose and serum lipids is not well defined. Objective: In this study we aimed to compare the levels of blood glucose, triacylglycerols, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol in patients with different stages of ovarian cancer and healthy controls to determine how they relate to the risk and prognosis of ovarian cancer. Methodology: In a case-control cross sectional study, we enrolled ninety-nine Sudanese women, diagnosed with ovarian cancer but had not received any kind of treatment as the study group, and a control group of forty-one age-matched, apparently healthy women. The patients were classified according to the International Federation of Obstetricians and Gynecologists staging system into two groups: early stages (stage I & II) and late stages (stages III & IV). Blood glucose and serum lipids;triacylglycerols, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol were determined by enzymatic colorimetric methods using commercially available analytical kits. The IBM SPSS version 20 software was used for statistical analysis. A Mann-Whitney U test was used for comparison of the median concentrations of blood glucose, triacylglycerols, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol in the study groups. Logistic regression model was used to estimate the relative risk of ovarian cancer in relation to levels of blood glucose and serum lipids. P value of 0.05 was considered significant. Results: Our data indicated significantly higher levels of blood glucose (p < 0.001), triacylglycerols (p = 0.002), and low-density lipoprotein cholesterol (p < 0.001), and lower levels of high-density lipoprotein cholesterol (p = 0.023), in ovarian cancer patients compared to the control subjects. No significant difference was found in the levels of blood glucose or any of the serum lipids between patients in the early stages (stage I & II) and those in late stages (stage III & IV) of ovarian cancer. The logistic regression analysis indicated significant association between the elevated levels of the blood glucose, triacylglycerols and low-density lipoprotein cholesterol and the risk of the ovarian cancer. Conclusion: We conclude that the levels of blood glucose, triacylglycerols, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol differ significantly between ovarian cancer patients and the healthy control subjects. The risk of ovarian cancer was positively associated with the levels of blood glucose, triacylglycerols and low-density lipoprotein cholesterol, and negatively associated with levels of high-density lipoprotein cholesterol. Therefore, determination of blood glucose and serum lipids, particularly, triacylglycerols, low-density lipoprotein cholesterol may be helpful as diagnostic indicators of ovarian cancer (OC).

Relationships among body weight,lipids and bone mass in elderly individuals with fractures:A case-control study

BACKGROUND The prevalence of osteoporosis and low bone mass is steadily rising each year.Low body weight is commonly linked to diminished bone mass and serves as a robust predictor of osteoporosis.Nonetheless,the connection between body mass index(BMI),bone mineral density,and lipid profiles among the elderly remains elusive.AIM To examine the association between BMI and bone mass,explore the correlation between lipid profiles and bone mass,and delve into the interplay between lipid metabolism and bone health.METHODS The study included 520 patients aged≥65 years(178 men and 342 women).Age,sex,weight,and height were recorded.Femoral neck bone mineral density and T scores were determined using a dual-energy X-ray absorptiometry scanner.Blood calcium(Ca),phosphorus(P),albumin(ALB),alkaline phosphatase(ALP),aspartate aminotransferase,alanine aminotransferase,triglyceride(TG),total cholesterol(TC),high-density lipoprotein(HDL)and low-density lipoprotein(LDL)levels were measured.Patients were classified by sex(male and female),age(65-79 years and≥80 years),and T score(normal bone mineral density,osteopenia and osteoporosis).RESULTS Age,sex,BMI,and ALP and TG levels were independent risk factors for osteoporosis.For the 65-79-and≥80-yearold groups,females presented lower T scores than males.Ca,P,ALB,ALP,TC,HDL and LDL levels were significantly different between men and women in the 65-79-year-old group.In addition,BMI and TG levels were significantly decreased in osteoporotic patients compared with patients with normal bone mass.TC levels declined in 65-to 79-year-old male and female osteoporosis patients.In the group of women aged≥80 years,osteoporotic patients showed significantly increased ALP levels.Furthermore,we found positive correlations between BMI and TG levels in the male and female patient groups.However,we found no significant differences in ALB,Ca,P,HDL and LDL levels in osteoporotic patients compared to patients with normal bone mass.CONCLUSION Osteoporotic patients showed significantly decreased BMI and TG levels compared with those with normal bone mass.BMI showed positive correlations with TG levels in male and female patients.These results indicate correlations between BMI and bone mass and between lipid profiles and bone mass.

The effects of smoking on blood lipids, C-reactive protein, and homocysteine in young patients with ischemic stroke

Objective:To investigate clinical signif-icance of the effects of smoking on blood lipids, C-reac-tive protein,and homocysteine in young ischemic stroke patients.Methods:The clinical data of 423 young stroke patients in the department of neurology at Taihe Hospi-tal in Shiyan City, China were retrospectively analyzed, including age,gender,drinking history,family history,and atrial fibrillation history. Patients were divided into two groups according to whether they smoked,and the blood lipids, C-reactive protein, and homocysteine were compared between groups.Results:The proportion of smokers was 41.83%.The levels of total cholesterol,tri-glycerides (TG), low density lipoprotein (LDL), and ho-mocysteine were higher in patients who smoked than in those who did not(P < 0.05). High density lipoprotein (HDL) was lower in the smoking group (P < 0.05). C-re-active protein test results were divided into groups ac-cording to whether the levels exceeded the normal range or not, and no correlation was found between C-reactive protein levels and smoking(P>0.05). Conclusion:Total cholesterol, TG, LDL, HDL, and homocysteine were sig-nificantly different between stroke patients who smoked and those who did not. We therefore suggest that smok-ing cessation take place as soon as possible and that it be avoided entirely in order to reduce the incidence of atherosclerosis and stroke.

Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous system.Lipid droplet formation begins with the synthesis of neutral lipids in the endoplasmic reticulum.Previously,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous system.In addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress responses.Furthermore,lipid droplets exhibit specific functions in neurons and glial cells.Dysregulation of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system diseases.This review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and functions.Additionally,it will explore the association between lipid droplets and neurodegenerative disorders.Understanding the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

Low-density lipoprotein receptor-related protein 2(LRP2)is required for lipid export in the midgut of the migratory locust,Locusta migratoria

Low-density lipoprotein receptor-related protein 2(LRP2)is a multifunctional endocytic receptor expressed in epithelial cells.In mammals,it acts as an endocytic receptor that mediates the cellular uptake of cholesterol-containing apolipoproteins to maintain lipid homeostasis.However,little is known about the role of LRP2 in lipid homeostasis in insects.In the present study,we investigated the function of LRP2 in the migratory locust Locusta migratoria(LmLRP2).The mRNA of LmLRP2 is widely distributed in various tissues,including integument,wing pads,foregut,midgut,hindgut,Malpighian tubules and fat body,and the amounts of LmLRP2 transcripts decreased gradually in the early stages and then increased in the late stages before ecdysis during the nymphal developmental stage.Fluorescence immunohistochemistry revealed that the LmLRP2 protein is mainly located in cellular membranes of the midgut and hindgut.Using RNAi to silence LmLRP2 caused molting defects in nymphs(more than 60%),and the neutral lipid was found to accumulate in the midgut and surface of the integument,but not in the fat body,of dsLmLRP2-treated nymphs.The results of a lipidomics analysis showed that the main components of lipids(diglyceride and triglyceride)were significantly increased in the midgut,but decreased in the fat body and hemolymph.Furthermore,the content of total triglyceride was significantly increased in the midgut,but markedly decreased in the fat body and hemolymph in dsLmLRP2-injected nymphs.Our results indicate that LmLRP2 is located in the cellular membranes of midgut cells,and is required for lipid export from the midgut to the hemolymphand fat body in locusts.

Lipid concentration and composition in xylem sap of woody angiosperms from a tropical savanna and a seasonal rainforest

Lipids may play an important role in preventing gas embolisms by coating nanobubbles in xylem sap.Few studies on xylem sap lipids have been reported for temperate plants,and it remain unclear whether sap lipids have adaptational significance in tropical plants.In this study,we quantify the lipid composition of xylem sap for angiosperm species from a tropical savanna(seven species)and a seasonal rainforest(five species)using mass spectrometry.We found that all twelve species studied contained lipids in their xylem sap,including galactolipids,phospholipids and triacylglycerol,with a total lipid concentration ranging from 0.09 to 0.26 nmol/L.There was no difference in lipid concentration or composition between plants from the two sites,and the lipid concentration was negatively related to species’open vessel volume.Furthermore,savanna species showed little variation in lipid composition between the dry and the rainy season.These results support the hypothesis that xylem sap lipids are derived from the cytoplasm of individual conduit cells,remain trapped inside individual conduits,and undergo few changes in composition over consecutive seasons.A xylem sap lipidomic data set,which includes 12 tropical tree species from this study and 11 temperate tree species from literature,revealed no phylogenetic signals in lipid composition for these species.This study fills a knowledge gap in the lipid content of xylem sap in tropical trees and provides additional support for their common distribution in xylem sap of woody angiosperms.It appears that xylem sap lipids have no adaptive significance.

Parboiled rice supplementation alleviates high-fat diet-induced hyperlipidemia by regulating genes and gut microbiota in mice

Dietary parboiled rice(PR)has a low risk of disease,but little is known about the contribution of PR to the prevention of hyperlipidemia.The potential role and underlying mechanisms of PR in hyperlipidemia were evaluated in this study.Male C57BL/6J mice were fed with a normal diet,high-fat diet(HFD)containing refined rice(HFDRR)or PR(HFDPR).It was found that PR intervention improved lipid accumulation in mice.Transcriptomic data analysis revealed that 27 genes were up-regulated(mostly involved in lipid breakdown)and 86 genes were down-regulated(mostly involved in inflammatory responses)in the HFDPR group compared to the HFDRR group.And 15 differentially expressed genes(DEGs)were validated by quantitative real-time PCR(RT-qPCR),while protein interaction network showed that protein tyrosine phosphatase receptor type C(PTPRC)has a central role.The gut microbiota of mice was also altered after different dietary treatments,with higher ratio of Firmicutes and Bacteroidetes,increased abundances of Ruminococcaceae,Lachnospiraceae,Christensenellaceae,Porphyromonadaceae,Rikenellaceae and Prevotellaceae,and decreased abundances of Lactobacillaceae,Peptostreptococcaceae,Erysipelotrichaceae and Actinobacteria in the HFDRR group.In addition,it was observed that PPAR signaling pathway may act as a bridge between DEGs and differential gut microbiota.These results suggested that PR can prevent hyperlipidemia by modulating liver genes and gut microbiota.

Supplementation of alanine improves biomass accumulation and lipid production of Chlorella pyrenoidosa by increasing the respiratory and metabolic processes

The function of exogenous alanine(Ala)in regulating biomass accumulation,lipid production,photosynthesis,and respiration in Chlorella pyrenoidosa was studied.Result shows that the supplementation of Ala increased C.pyrenoidosa biomass and lipid production in an 8-d batch culture.The concentration of 10 mmol/L of Ala was optimum and increased the microalgal cell biomass and lipid content by 39.3%and 21.4%,respectively,compared with that in the control(0-mmol/L Ala).Ala supplementation reduced photosynthetic activity while boosting respiratory activity and pyruvate levels,indicating that C.pyrenoidosa used exogenous Ala for biomass accumulation through the respiratory metabolic process.The accelerated respiratory metabolism due to Ala supplementation elevated the substrate pool and improved the lipogenic gene expression,promoting lipid production at last.This study provided a novel method for increasing biomass accumulation and lipid production and elucidated the role of Ala in regulating lipid production.

Molecular dynamics simulations on the interactions between nucleic acids and a phospholipid bilayer

Recently,lipid nanoparticles(LNPs)have been extensively investigated as non-viral carriers of nucleic acid vaccines due to their high transport efficiency,safety,and straightforward production and scalability.However,the molecular mechanism underlying the interactions between nucleic acids and phospholipid bilayers within LNPs remains elusive.In this study,we employed the all-atom molecular dynamics simulation to investigate the interactions between single-stranded nucleic acids and a phospholipid bilayer.Our findings revealed that hydrophilic bases,specifically G in single-stranded RNA(ssRNA)and single-stranded DNA(ssDNA),displayed a higher propensity to form hydrogen bonds with phospholipid head groups.Notably,ssRNA exhibited stronger binding energy than ssDNA.Furthermore,divalent ions,particularly Ca2+,facilitated the binding of ssRNA to phospholipids due to their higher binding energy and lower dissociation rate from phospholipids.Overall,our study provides valuable insights into the molecular mechanisms underlying nucleic acidphospholipid interactions,with potential implications for the nucleic acids in biotherapies,particularly in the context of lipid carriers.