Fluorescent probes for glucolipid metabolism of bacterial cell wall

Cell wall is a basic component of bacteria that promotes bacteria to adapt the complicated environment as well as play an essential role in antimicrobial resistance.The structure of bacterial cell wall is remarkably rich,and some complex components,such as peptidoglycan,lipopolysaccharide,and peptidoglycan-arabinogalactan et al.,can only be found in bacteria.Furthermore,the biosynthesis and transfer of these glycolipids are indispensable for bacteria during cell elongation.And the process of biosynthesis and transfer are generally associated with metabolism and sophisticated enzyme mechanisms.However,how the metabolic process takes place,what role enzymes play in this process and how they function have been major concerns for scientists in this field.Numerous significant progresses on fluorescent probes and biological imaging bring opportunity for the studying of metabolism and enzyme mechanisms recently due to its non-invasive and high sensitivity.In this review,we focused on metabolic fluorescent probes for the detection of glycolipids in bacterial cell wall and highlighted the involving mechanisms and biological application.

Activating transcription factor 3,glucolipid metabolism,and metabolic diseases

Lipids and glucose exert many essential physiological functions,such as providing raw materials or energy for cellular biosynthesis,regulating cell signal transduction,and maintaining a constant body temperature.Dysregulation of lipid and glucose metabolism can lead to glucolipid metabolic disorders linked to various metabolic diseases,such as obesity,diabetes,and cardiovascular disease.Therefore,intervention in glucolipid metabolism is a key therapeutic strategy for the treatment of metabolic diseases.Activating transcription factor 3(ATF3)is a transcription factor that acts as a hub of the cellular adaptive-response network and plays a pivotal role in the regulation of inflammation,apoptosis,DNA repair,and oncogenesis.Emerging evidence has illustrated the vital roles of ATF3 in glucolipid metabolism.ATF3 inhibits intestinal lipid absorption,enhances hepatic triglyceride hydrolysis and fatty acid oxidation,promotes macrophage reverse cholesterol transport,and attenuates the progression of western diet-induced nonalcoholic fatty liver disease and atherosclerosis.In addition to its role in lipid metabolism,ATF3 has also been identified as an important regulator of glucose metabolism.Here,we summarize the recent advances in the understanding of ATF3,mainly focusing on its role in glucose and lipid metabolism and potential therapeutic implications.

Intrauterine growth retardation affects liver bile acid metabolism in growing pigs:effects associated with the changes of colonic bile acid derivatives

Background:Intrauterine growth retardation(IUGR)is associated with severely impaired nutrient metabolism and intestinal development of pigs.Our previous study found that IUGR altered intestinal microbiota and metabolites in the colon.However,the consequences of IUGR on bile acid metabolism in pigs remained unclear.The present study aimed to investigate the bile acid metabolism in the liver and the profile of bile acid derivatives in the colon of grow-ing pigs with IUGR using bile acid targeted metabolomics.Furthermore,we determined correlations between colonic microbiota composition and metabolites of IUGR and normal birth weight(NBW)pigs at different growth stages that were 7,21,and 28-day-old,and the average body weight(BW)of 25,50,and 100 kg of the NBW pigs.Results:The results showed that the plasma total bile acid concentration was higher(P<0.05)at the 25 kg BW stage and tended to increase(P=0.08)at 28-day-old in IUGR pigs.The hepatic gene expressions related to bile acid synthe-sis(CYP7A1,CYP27A1,and NTCP)were up-regulated(P<0.05),and the genes related to glucose and lipid metabolism(ATGL,HSL,and PC)were down-regulated(P<0.05)at the 25 kg BW stage in IUGR pigs when compared with the NBW group.Targeted metabolomics analysis showed that 29 bile acids and related compounds were detected in the colon of pigs.The colonic concentrations of dehydrolithocholic acid and apocholic acid were increased(P<0.05),while isodeoxycholic acid and 6,7-diketolithocholic acid were decreased(P<0.05)in IUGR pigs,when compared with the NBW pigs at the 25 kg BW stage.Moreover,Spearman’s correlation analysis revealed that colonic Unclassified_[Mogi-bacteriaceae],Lachnospira,and Slackia abundances were negatively correlated(P<0.05)with dehydrolithocholic acid,as well as the Unclassified_Clostridiaceae abundance with 6,7-diketolithocholic acid at the 25 kg BW stage.Conclusions:These findings suggest that IUGR could affect bile acid and glucolipid metabolism in growing pigs,especially at the 25 kg BW stage,these effects being paralleled by a modification of bile acid derivatives concentra-tions in the colonic content.The plausible links between these modified parameters are discussed.

Relationship between serum osteocalcin levels and glucolipid metabolism in elderly type 2 diabetic patients with non-alcoholic fatty liver disease

Objective To explore the relationship between serum osteocalcin levels and glucolipid metabolism in elderly type 2 diabetic patients with non-alcoholic fatty liver disease(NAFLD).Methods Data collected from 97 pa-tients with type 2 diabetes mellitus(T2DM)admitted to the Department of Geriatric Endocrinology of the First Affiliated hospital of Zhengzhou University from June

Study on the Correlation Between SFRP-5 Expression Level, Insulin Resistance, and Glycolipid Metabolism in Gestational Diabetes Mellitus

Objective:To investigate the correlation between serum secretory frizzled-related protein 5(SFRP-5)expression levels and insulin resistance and glucolipid metabolism in patients with gestational diabetes mellitus(GDM).Methods:Baseline data were collected from 58 patients with GDM and 51 healthy controls who were admitted Affiliated Hospital of Hebei University from May 2020 to June 2022.sSTRA5 concentrations in peripheral blood of pregnant women were measured,and SFRP-5 levels in patients with different GDM types and normal controls were analyzed by logistic regression models.Results:The levels of triglyceride(TG),total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),fasting blood glucose(FBG),fasting insulin(FINS),hemoglobin A1c(HbA1c),and homeostasis model assessment-estimated insulin resistance(HOMA-IR)were higher in the observation group than in the control group,with statistically significant differences(P<0.05),while the expression levels of high-density lipoprotein cholesterol(HDL-C)and serum SFRP-5 were lower than in the control group,with statistically significant differences(P<0.05);serum SFRP-5,TG,TC,FBG,and HOMA-IR were all risk factors for GDM(P<0.05).Conclusion:Elevated serum sSTRA5 may be involved in the regulation of insulin resistance in the body and the regulation of blood glucose in the body by affecting lipid metabolism and inflammatory response.

Dietary fat supplementation relieves cold temperature-induced energy stress through AMPK-mediated mitochondrial homeostasis in pigs

Background Cold stress has negative effects on the growth and health of mammals, and has become a factor restricting livestock development at high latitudes and on plateaus. The gut-liver axis is central to energy metabolism, and the mechanisms by which it regulates host energy metabolism at cold temperatures have rarely been illustrated. In this study, we evaluated the status of glycolipid metabolism and oxidative stress in pigs based on the gut-liver axis and propose that AMP-activated protein kinase(AMPK) is a key target for alleviating energy stress at cold temperatures by dietary fat supplementation.Results Dietary fat supplementation alleviated the negative effects of cold temperatures on growth performance and digestive enzymes, while hormonal homeostasis was also restored. Moreover, cold temperature exposure increased glucose transport in the jejunum. In contrast, we observed abnormalities in lipid metabolism, which was characterized by the accumulation of bile acids in the ileum and plasma. In addition, the results of the ileal metabolomic analysis were consistent with the energy metabolism measurements in the jejunum, and dietary fat supplementation increased the activity of the mitochondrial respiratory chain and lipid metabolism. As the central nexus of energy metabolism, the state of glycolipid metabolism and oxidative stress in the liver are inconsistent with that in the small intestine. Specifically, we found that cold temperature exposure increased glucose transport in the liver, which fully validates the idea that hormones can act on the liver to regulate glucose output. Additionally, dietary fat supplementation inhibited glucose transport and glycolysis, but increased gluconeogenesis, bile acid cycling, and lipid metabolism. Sustained activation of AMPK, which an energy receptor and regulator, leads to oxidative stress and apoptosis in the liver;dietary fat supplementation alleviates energy stress by reducing AMPK phosphorylation.Conclusions Cold stress reduced the growth performance and aggravated glycolipid metabolism disorders and oxidative stress damage in pigs. Dietary fat supplementation improved growth performance and alleviated cold temperature-induced energy stress through AMPK-mediated mitochondrial homeostasis. In this study, we high-light the importance of AMPK in dietary fat supplementation-mediated alleviation of host energy stress in response to environmental changes.

Inonotus obliquus(Chaga)against HFD/STZ-induced glucolipid metabolism disorders and abnormal renal functions by regulating NOS-cGMP-PDE5 signaling pathway

Our prior investigations have established that Inonotus obliquus(Chaga)possesses hypoglycemic effects.Persistent hyperglycemia is known to precipitate renal function abnormalities.The functionality of the kidneys is intricately linked to the levels of cyclic guanosine-3',5'-monophosphate(cGMP),which are influenced by the activities of nitric oxide synthase(NOS)and phosphodiesterase(PDE).Enhanced cGMP levels can be achieved either through the upregulation of NOS activity or the downregulation of PDE activity.The objective of the current study is to elucidate the effects of Chaga on disorders of glucolipid metabolism and renal abnormalities in rats with type 2 diabetes mellitus(T2DM),while concurrently examining the NOS-cGMP-PDE5 signaling pathway.A model of T2DM was developed in rats using a high-fat diet(HFD)combined with streptozotocin(STZ)administration,followed by treatment with Chaga extracts at doses of 50 and 100 mg·kg^(−1)for eight weeks.The findings revealed that Chaga not only mitigated metabolic dysfunctions,evidenced by improvements in fasting blood glucose,total cholesterol,triglycerides,and insulin resistance,but also ameliorated renal function markers,including serum creatinine,urine creatinine(UCr),blood urea nitrogen,24-h urinary protein,and estimated creatinine clearance.Additionally,enhancements in glomerular volume,GBM thickness,podocyte foot process width(FPW),and the mRNA and protein expressions of podocyte markers,such as nephrin and wilms tumor-1,were observed.Chaga was found to elevate cGMP levels in both serum and kidney tissues by increasing mRNA and protein expressions of renal endothelial NOS and neural NOS,while simultaneously reducing the expressions of renal inducible NOS and PDE5.In summary,Chaga counteracts HFD/STZ-induced glucolipid metabolism and renal function disturbances by modulating the NOS-cGMP-PDE5 signaling pathway.This research supports the potential application of Chaga in the clinical prevention and treatment of T2DM and diabetic nephropathy(DN),with cGMP serving as a potential therapeutic target.

Liver-Adipose Tissue Crosstalk:A Key Player in the Pathogenesis of Glucolipid Metabolic Disease

Glucolipid metabolic disease （GLMD）, a complex of interrelated disorders in glucose and lipid metabolism, has become one of the leading chronic diseases causing public and clinical problem worldwide. As the metabolism of lipid and glucose is a highly coordinated process under both physiological and diseased conditions, the impairment in the signals corresponding to the metabolism of either lipid or glucose represents the common mechanism underlying the pathogenesis of GLMD. The liver and adipose tissue are the major metabolic organs responsible for energy utilization and storage, respectively. This review article aims to summarize the current advances in the investigation of the functional roles and the underling mechanisms of the interplay between the liver and adipose tissue in the modulation of GLMD development. Fibroblast growth factor 21 （FGF21） and adiponectin represent the two major hormones secreted from the liver and adipose tissues, respectively. FGF21 exerts pleiotropic effects on regulating glucose and lipid homeostasis majorly through inducing the expression and secretion of adiponectin. Therefore, FGF21-adiponectin axis functions as the key mediator for the crosstalk between the liver and adipose tissue to exert the beneficial effects on the maintenance of the homeostasis of energy consumption. The liver- and adipose tissue-derived factors with pleiotropic effects on regulating of lipid and glucose metabolism function as the key mediator for the crosstalk between these two highly active metabolic organs, thereby coordinating the initiation and development of GLMD.

Research Progress on Prevention and Treatment of Glucolipid Metabolic Disease with Integrated Traditional Chinese and Western Medicine

Hyperlipidemia, type 2 diabetes mellitus, nonalcoholic fatty liver and many other metabolic disorder are frequently co-existing in patients. In addition, these diseases are closely related in pathophysiological settings. However, increasing of the disease incidence, lacking of comprehensive prevention and control measurements against the key pathology point concomitant occurrence with the pattem of the single disease, single target therapy, that is leading therapeutic strategy for these metabolic disorders in the setting of Western medicine （WM）. On the basis of the combination of the advantages of integrated Chinese medicine （CM） and WM, with unified understanding of such diseases, the new concept of glucolipid metabolic disease （GLMD） is introduced. In this new concept, disorders in glucose and lipid metabolism are recognized as the key trigger and major driving force for the progress of GLMD. The key points of pathology included dysfunction of neuronal-endocrine-immune system,insulin resistance, oxidative stress, inflammation and intestinal flora imbalance. In the core pathogenic perspective of CM, it can be explained as ＂Gan （Liver） Shi Shu Xie＂ （dysfunction of Gan in metabolism and emotion regulation） that will lead to the occurence/production of endogenous dampness and phlegm, blood stasis and turbid. This leads to the new concept of ＂Liver-based regulatory system for metabolic homeostasis＂ to be introduced further. The comprehensive prevention and control strategy ＂Tiao Gan Qi Shu Hua Zhuo＂ （modulating Gan, trigging key metabolic system to resolve pathogenic factors such as phlegm retention and dampness）. Its representative formula Fufang Zhenzhu Tiaozhi Capsule （复方贞术调脂胶囊） is innovated under such rationales. Comment for some commonly-used CM GLMD therapeutic drugs was presented. High-level evidence-based and epidemiological and mechanism studies should be carded out to further interpret and explain of the scientific connotation of GLMD.

Sex-dependent obesogenic effect of tetracycline on Drosophila melanogaster deteriorated by dysrhythmia

Antibiotics have been identified as obesogens contributing to the prevalence of obesity.Moreover,their environmental toxicity shows sex dependence,which might also explain the sex-dependent obesity observed.Yet,the direct evidence for such a connection and the underlying mechanisms remain to be explored.In this study,the effects of tetracycline,which is a representative antibiotic found in both environmental and food samples,on Drosophila melanogaster were studied with consideration of both sex and circadian rhythms(represented by the eclosion rhythm).Results showed that in morning-eclosed adults,tetracycline significantly stimulated the body weight of females(AM females)at 0.1,1.0,10.0 and 100.0μg/L,while tetracycline only stimulated the body weight of males(AM males)at 1.0μg/L.In the afternoon-eclosed adults,tetracycline significantly stimulated the body weight of females(PM females)at 0.1,1.0 and 100.0μg/L,while it showed more significant stimulation in males(PM males)at all concentrations.Notably,the stimulation levels were the greatest in PMmales among all the adults.The results showed the clear sex dependence of the obesogenic effects,which was diminished by dysrhythmia.Further biochemical assays and clustering analysis suggested that the sex-and rhythm-dependent obesogenic effects resulted from the bias toward lipogenesis against lipolysis.Moreover,theywere closely related to the preference for the energy storage forms of lactate and glucose and also to the presence of excessive insulin,with the involvement of glucolipid metabolism.Such relationships indicated potential bridges between the obesogenic effects of pollutants and other diseases,e.g.,cancer and diabetes.