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Neuregulins (NRGs) are a family of signaling proteins that bind to receptor tyrosine kinases of the ErbB family (ErbB2 to ErbB4), which can homo- or heterodimerize depending on their structural features and cell type. Many studies have proposed that decreased NRG levels are a common characteristic of obesity. In liver and adipose tissue, the increase in NRG expression has protective effects against obesity. However, it is still unknown whether ErbBs expression is altered in this pathology. We hypothesized that high fat diet-induced obesity downregulates ErbB receptors expression in obese mice compared to normal weight mice. Males C57BL/6 mice (n=6-7 for each group) were fed for 12 weeks and divided into: (i) control diet (CD; 10%-kcal fat, 20%-kcal protein, 70%-kcal carbohydrates), and (ii) high fat diet (HFD; 60%-kcal fat, 20%-kcal protein, 20%-kcal carbohydrates). General parameters and ErbBs expression (qPCR, immunohistochemistry and Western blot) were evaluated. We observed a significant increase in final body weight (47%), adipose tissue to body weight ratio (244%) and HOMA-IR (69%), among other parameters, in obese mice. In HFD group significantly decreased ErbB2 (48%) and ErbB3 (66%) mRNA levels in liver (no change in ErbB4), and ErbB2 (43%), ErbB3 (76%) and ErbB4 (35%) in adipose tissue, compared to CD. Furthermore, ErbB2 and ErbB3 protein levels decreased significantly in HFD group compared to the CD in liver. Therefore, our results suggest that HFD-induced obesity significantly decreases ErbBs expression in liver and adipose tissue in this murine model, that may be associated with alterations in the NRG pathway in obese mice.
Las neuregulinas (NRGs) son una familia de proteínas de señalización que se unen a receptores tirosina quinasas de la familia ErbB (ErbB2 a ErbB4), que pueden homo- o heterodimerizar dependiendo de sus características estructurales y del tipo celular. Estudios han propuesto que la disminución de los niveles de NRG es una característica común de la obesidad. En el hígado y el tejido adiposo (TA), el aumento de la expresión de NRG tiene efectos protectores contra la obesidad. Sin embargo, aún se desconoce si la expresión de ErbBs está alterada en esta patología. Nuestra hipótesis es que la obesidad inducida por una dieta alta en grasas (DAG) disminuye la expresión de los ErbB en ratones obesos. Ratones machos C57BL/6 (n=6-7 para c/grupo) fueron alimentados durante 12 semanas y divididos en: (i) dieta control (DC; 10%-kcal grasa, 20%-kcal proteína, 70%-kcal carbohidratos), y (ii) DAG (60%-kcal grasa, 20%-kcal proteína, 20%-kcal carbohidratos). Se evaluaron los parámetros generales y la expresión de ErbBs (qPCR, inmunohistoquímica y Western blot). Observamos un aumento significativo del peso corporal final (47%), de la relación tejido adiposo/peso corporal (244%) y del HOMA-IR (69%), entre otros parámetros, en ratones obesos. En este grupo disminuyó significativamente los niveles de ARNm de ErbB2 (48%) y ErbB3 (66%) en el hígado (sin cambios en ErbB4), y de ErbB2 (43%), ErbB3 (76%) y ErbB4 (35%) en el TA. Además, los niveles de proteína ErbB2 y ErbB3 disminuyeron significativamente, en comparación con el grupo DC en el hígado. Nuestros resultados sugieren que la obesidad inducida por DAG disminuye significativamente la expresión de ErbBs en el hígado y el TA, que puede estar asociado con alteraciones en la vía NRG en ratones obesos.
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ABSTRACT BACKGROUND: The effect of weight loss (WL) on histopathological aspects of non-alcoholic fatty liver disease (NAFLD) may provide further insights into the dynamics of hepatic recovery after WL. OBJECTIVE: To analyze the effects of pre-operative WL on insulin resistance- and NAFLD-related histology in individuals undergoing bariatric surgery (BS) with or without pre-operative WL. DESIGN AND SETTING: A matched cross-sectional study was conducted at a public university hospital and a private clinic in Campinas, Brazil. METHODS: An analytical, observational, cross-sectional study was conducted using prospectively collected databases of individuals who underwent BS and liver biopsy at either a public tertiary university hospital (with pre-operative WL) or a private clinic (without pre-operative WL). Random electronic matching by gender, age, and body mass index (BMI) was performed and two paired groups of 24 individuals each were selected. RESULTS: Of the 48 participants, 75% were female. The mean age was 37.4 ± 9.6. The mean BMI was 38.9 ± 2.6 kg/m2. Fibrosis was the most common histopathological abnormality (91.7%). Glucose was significantly lower in the WL group (92 ± 19.1 versus 111.8 ± 35.4 mg/dL; P = 0.02). Significantly lower frequencies of macrovesicular steatosis (58.3% versus 95.8%; P = 0.004), microvesicular steatosis (12.5% versus 87.5%; P < 0.001), and portal inflammation (50% versus 87.5%; P = 0.011) were observed in the WL group. CONCLUSION: Pre-operative WL was significantly associated with lower frequencies of macro- and mi- crovesicular steatosis, portal inflammation, and lower glycemia, indicating an association between the recent trajectory of body weight and histological aspects of NAFLD.
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ABSTRACT Objective: Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease and a growing global epidemic. In NAFLD, liver fat surpasses 5% of hepatocytes without the secondary causes of lipid accumulation or excessive alcohol consumption. Given the link between NAFLD and insulin resistance, the possible association between the rs2854744 (−202 G>T) promoter polymorphism of insulin-like growth factor binding protein 3 (IGFBP3) gene and NAFLD was investigated in this study. Materials and methods: In this genetic case-control association study, the IGFBP3 rs2854744 genotypes of 315 unrelated individuals, including 156 patients with biopsy-proven NAFLD and 159 controls, were determined using polymerase chain reaction/restriction fragment length polymorphism analyses. Results: The "GT+TT" genotype of the IGFBP3 rs2854744 polymorphism, compared with the "GG" genotype, was associated with a 2.7-fold increased risk of NAFLD after adjustment for confounding factors (P = 0.009; odds ratio [OR] = 2.71; 95% confidence interval [CI] = 1.19-3.18). Additionally, the IGFBP3 rs2854744 "T" allele, in comparison with the "G" allele, was significantly overrepresented in NAFLD patients than the controls (P = 0.008; OR = 1.85; 95%CI = 1.23-2.94). Conclusion: Our findings first indicated that the IGFBP3 rs2854744 "GT+TT" genotype is a marker of increased NAFLD susceptibility; however, it needs to be supported by further investigations in other populations.
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ABSTRACT Objective: To assess the association between leptin/adiponectin ratio (LAR) and insulin resistance surrogates in prepubertal children. Subjects and methods: Study based on data from the Growth and Obesity Chilean Cohort Study (GOCS) involving 968 Chilean prepubertal children. Plasma insulin, leptin, and adiponectin were determined by immunoassays. Several common insulin resistance surrogates were calculated, including the homeostasis model assessment of insulin resistance (HOMA-IR), triglyceride/HDL cholesterol index, triglyceride-glucose (TyG) index, and the TyG index corrected for body mass index (BMI; TyG-BMI) and waist circumference (WC; TyG-WC). Associations among variables were assessed using multiple linear and logistic regression analysis. Results: There was a significant direct association between plasma leptin and LAR with BMI z-score but no association between plasma adiponectin and adiposity. After adjustments for sex and age, LAR was significantly associated with all insulin resistance surrogates (which were categorized using the 75th percentile as the cutoff point), with the TyG-WC index emerging as the surrogate with the highest magnitude of association (odds ratio [OR] 2.44, 95% confidence interval [CI] 2.05-2.9). After additional adjustment for BMI z-score, only the association between LAR and TyG-WC remained significant (OR 1.64, 95% CI 1.27-2.12). Conclusion: Plasma leptin and LAR were strongly associated with several common insulin resistance surrogates in prepubertal children, most notably with the TyG-WC index. Associations between LAR and insulin resistance indexes were mainly driven by the effect of plasma leptin, which is also directly associated with increased adiposity.
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ABSTRACT Objective: To evaluate the effects of medical education on hospital hyperglycemia on physician's technical knowledge and the quality of medical prescriptions, patient care, and clinical outcomes. Subjects and methods: The intervention included online classes and practical consultations provided by an endocrinologist to medical preceptors and residents of the Department of Internal Medicine. A pretest and a post-test (0 to 10 points) were applied before and after the intervention and patients medical records were reviewed before and after the intervention. The outcomes were improvement in medical knowledge, in the quality of prescriptions for patients in the clinical area, and clinical outcomes. Results: The global mean of correct answers improved with the intervention [before: 6.9 points (±1.7) versus after the intervention: 8.8 points (±1.5) (p < 0.001)]. The number of patients who did not have at least one blood glucose assessment during the entire hospitalization for acute illness decreased from 12.6% before to 2.6% (p < 0.001) after the intervention. There was also a significant reduction in hospital hypoglycemia rates (p < 0.026). The use of sliding-scale insulin as the main treatment was quite low before and after the intervention (2.2% and 0%). After 6 months, medical knowledge did not show significant reduction. Conclusion: Medical education on hospital hyperglycemia can improve medical knowledge and clinical outcomes for patients. The improvement in medical knowledge was maintained after 6 months.
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ABSTRACT. The disability of cells to react to insulin, causing glucose intolerance and hyperglycemia, is referred to as insulin resistance. This clinical condition, which has been well-researched in organs such as adipose tissue, muscle, and liver, has been linked to neurodegenerative diseases like Alzheimer's disease (AD) when it occurs in the brain. Objective: The authors aimed to gather data from the current literature on brain insulin resistance (BIR) and its likely repercussions on neurodegenerative disorders, more specifically AD, through a systematic review. Methods: A comprehensive search was conducted in multiple medical databases, including the Cochrane Central Register of Controlled Trials, EMBASE, Medical Literature Analysis and Retrieval System Online (Medline), and PubMed®, employing the descriptors: "insulin resistance", "brain insulin resistance", "Alzheimer's disease", "neurodegeneration", and "cognition". The authors focused their search on English-language studies published between 2000 and 2023 that investigated the influence of BIR on neurodegenerative disorders or offered insights into BIR's underlying mechanisms. Seventeen studies that met the inclusion criteria were selected. Results: The results indicate that BIR is a phenomenon observed in a variety of neurodegenerative disorders, including AD. Studies suggest that impaired glucose utilization and uptake, reduced adenosine triphosphate (ATP) production, and synaptic plasticity changes caused by BIR are linked to cognitive problems. However, conflicting results were observed regarding the association between AD and BIR, with some studies suggesting no association. Conclusion: Based on the evaluated studies, it can be concluded that the association between AD and BIR remains inconclusive, and additional research is needed to elucidate this relationship.
RESUMO. A incapacidade das células de reagir à insulina, ocasionando intolerância à glicose e hiperglicemia, é chamada de resistência à insulina. Essa condição clínica, que tem sido bem pesquisada em órgãos como tecido adiposo, músculo e fígado, tem sido associada às doenças neurodegenerativas como a doença de Alzheimer (DA) quando ocorre no cérebro. Objetivo: O objetivo dos autores foi reunir os dados da literatura atual sobre a resistência insulínica cerebral (RIC) e sua provável repercussão em doenças neurodegenerativas, mais especificamente na DA, por meio de uma revisão sistemática da literatura. Métodos: Foi realizada uma pesquisa abrangente em vários bancos de dados médicos, incluindo o Cochrane Central Register of Controlled Trials, EMBASE, Medical Literature Analysis and Retrieval System Online (Medline) e PubMed, empregando os descritores: "resistência à insulina", "resistência insulínica cerebral", "doença de Alzheimer", "neurodegeneração" e "cognição". Os autores concentraram sua busca em estudos no idioma inglês publicados entre 2000 e 2023 que investigaram a influência da RIC em distúrbios neurodegenerativos ou ofereceram insights sobre os mecanismos subjacentes da RIC. Dezessete estudos que atenderam aos critérios de inclusão foram selecionados. Resultados: Os resultados demonstram que a RIC é um fenômeno observado em uma variedade de doenças neurodegenerativas, incluindo a DA. Estudos sugerem que a utilização e captação prejudicadas de glicose, a produção reduzida de trifosfato de adenosina (ATP) e as alterações na plasticidade sinápticas causadas pela RIC estão ligadas a problemas cognitivos. No entanto, foram observados resultados conflitantes com relação à associação entre DA e RIC, com alguns estudos sugerindo nenhuma associação. Conclusão: Com base nos estudos avaliados, pode-se concluir que a associação entre DA e RIC ainda é inconclusiva, e pesquisas adicionais são necessárias para elucidar essa relação.
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Background: Scientific information on the impact of malaria on the risk of developing type 2 diabetes mellitus (T2DM) after recovery from the coronavirus disease 2019 (COVID-19) is limited in the Ghanaian context. The purpose of this study was to examine the association between selected risk markers of T2DM in falciparum malaria patients post-COVID-19 or not at a tertiary hospital in Ghana. Methodology: This was a descriptive cross-sectional comparative study of 38-recovered COVID-19 adult participants with malaria and 40 unexposed COVID-19 adults with malaria at the Tamale Teaching Hospital, Ghana. Demographic, anthropometric and levels of glucose, insulin, C-reactive protein and lipid profiles were measured in the two groups of participants under fasting conditions. Parasitaemia was assessed microscopically but insulin resistance and beta-cell function were assessed by the homeostatic model. Results: The COVID-19 exposed participants were older (p=0.035) with lower parasitaemia (p=0.025) but higher mean levels of insulin, insulin resistance, and beta-cell function compared with their unexposed counterparts (p<0.05). Parasitaemia correlated positively with a number of the measured indices of diabetogenic risk markers in the COVID-19 exposed group only, and predicted (Adjusted R2=0.751; p=0.031) by beta-cell function, C-reactive protein and triglycerides with the model explaining about 75% of the observed variation. Parasitaemia could only be predicted (Adjusted R2=0.245; p=0.002) by C-reactive protein with the model explaining just about a quarter of the observed variation in the COVID-19 unexposed group. Insulin resistance and sub-optimal beta-cell function were detected in both groups of participants. Conclusion: Falciparum malaria is associated with risk markers for development of T2DM irrespective of COVID-19 exposure. Insulin resistance, inflammation and sub-optimal beta-cell secretory function may drive the risk. The observed diabetogenic risk is higher in the recovered COVID-19 participants.
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Humans , Male , Female , Malaria, Falciparum , Diabetes Mellitus, Type 2 , COVID-19 , Inflammation , Risk FactorsABSTRACT
ObjectiveTo investigate the value of serum Fetuin-A and Fetuin-B combined with Homeostasis Model Assessment of Insulin Resistance （HOMA-IR） in predicting nonalcoholic fatty liver disease （NAFLD）. MethodsA total of 120 patients with NAFLD who attended Department of Gastroenterology， The First Affiliated Hospital of Dali University， from June 2020 to June 2021， and 120 healthy individuals who underwent physical examination at Physical Examination Center during the same period of time were enrolled as subjects， and clinical data were collected from all subjects. The serum levels of Fetuin-A and Fetuin-B were measured. The independent-samples t test or the Mann-Whitney U test was used for comparison of continuous data between two groups， and the chi-square test was used for comparison of categorical data between two groups； the multivariate Logistic regression analysis was used to assess the risk factors for NAFLD. The receiver operating characteristic （ROC） curve was plotted to evaluate the predictive efficacy of Fetuin-A and Fetuin-B combined with HOMA-IR in NAFLD patients. ResultsCompared with the healthy control group， the NAFLD group had significantly higher levels of body mass index， systolic blood pressure， diastolic blood pressure， alanine aminotransferase， aspartate aminotransferase， fasting blood glucose， fasting insulin， triglycerides， HOMA-IR， Fetuin-A， and Fetuin-B （all P<0.05）. The multivariate Logistic regression analysis showed that Fetuin-A （odds ratio ［OR］=1.010， 95% confidence interval ［CI］： 1.001 — 1.020， P<0.05）， Fetuin-B （OR=1.113， 95%CI： 1.021 — 1.214， P<0.05）， and HOMA-IR （OR=24.053， 95%CI： 2.624 — 220.470， P<0.05） were independent risk factors for NAFLD. The ROC curve analysis showed that Fetuin-A， Fetuin-B or HOMA-IR alone had an area under the ROC curve （AUC） of 0.637 （95%CI： 0.551 — 0.722）， 0.853 （95%CI： 0.796 — 0.912）， and 0.837 （95%CI： 0.763 — 0.912）， respectively， and Fetuin-A combined with Fetuin-B， Fetuin-A combined with HOMA-IR， and Fetuin-B combined with HOMA-IR had an AUC of 0.853 （95%CI： 0.795 — 0.911）， 0.843 （95%CI： 0.770 — 0.916）， 0.922 （95%CI： 0.877 — 0.967）， respectively， while the combination of these three indicators had an AUC of 0.922 （95%CI： 0.877 — 0.966）. ConclusionFetuin-A and Fetuin-B have a certain value in predicting NAFLD， and Fetuin-B combined with HOMA-IR tends to have a higher predictive value.
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ObjectiveTo explore the effect of precocious puberty on glucose metabolism and lipid metabolism in female rats. MethodsSixty two-day-old female rats were randomly divided into 2 groups. When aged 5 days， the precocious puberty group and normal group were given a single subcutaneous injection of danazol and solvent soybean oil respectively. The vaginal opening of rats was monitored from their 21 days of age. After 12 hours of fasting， all successful modeling rats were randomly executed within 3 days after vaginal opening， when aged 7 and 12 weeks. Then we measured the rats’ body weight and length， determined the concentrations of glucose， insulin， blood lipids， estradiol， leptin and adiponectin with enzyme-linked immunosorbent assay and observed the pathological changes of perirenal fat， uterus and ovary. ResultsFor body weight and length， rats in the precocious puberty group were smaller than those in the normal group within 3 days after vaginal opening， but which did not affect their subsequent growth and development， and there was no significant difference between the two groups at 7 and 12 weeks of age. Within 3 days after vaginal opening， insulin levels had significant difference between the two groups （P = 0.001）， the precocious group showed hyperinsulinemia and increased number of perirenal adipocytes. At three execution times， no significant difference was noted in estradiol， leptin and adiponectin levels between the two groups. The same was true in the ratios of ovary or uterus to body weight between the two groups. ConclusionsPrecocious puberty makes earlier onset of pubertal development and allows body maladaptation to the sudden changes of the internal environment. However， the changes due to precocious puberty are temporary and reversible， and they may become normal in adulthood.
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AIM: To study the effect and mechanism of Di'ao Xinxuekang (DXXK) on insulin resistance in nonalcoholic steatohepatitis (NASH) mice. METHODS: C57BL/6J mice were randomly divided into normal group and model group. After 16 weeks of high-fat diet, the model group was randomly divided into model group and Pioglitazone group (6.0 mg · kg
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AIM: To observe the real world efficacy of continuous subcutaneous insulin infusion (CSII) with insulin pump in short-term intensive treatment of patients with type 2 diabetes (T2DM) and explore the influencing factors associated with efficacy. METHODS: A total of 369 hospitalized T2DM patients were treated with CSII short-term intensive therapy. Based on the blood glucose levels on the 5th day of treatment, they were divided into two groups, namely the qualified blood glucose control group and the non-qualified blood glucose control group. The differences of glucose metabolism, physiology, biochemistry and other indicators between the two groups were compared, and the influencing factors of insulin pump efficacy were analyzed by regression statistics. RESULTS: After 4 days of CSII short-term treatment, 225 patients (61%) achieved blood glucose control standards, while 144 patients (39%) did not achieve blood glucose control standards. Compared with the qualified blood glucose control group, the non-qualified blood glucose control group was older and with higher levels of total daily insulin dose per kilogram of body weight (TDD), fasting blood glucose (FBG), fasting insulin, fasting C-peptide, and insulin resistance index (HOMA-IR), while lower levels of blood phosphorus, insulin growth factor 1 (IGF1). In terms of biochemical indicators, there was no significant difference between the two groups as a whole, including blood lipid levels, liver function, and kidney function. The results of univariate regression and multivariate stepwise regression analysis showed that 2-hour postprandial insulin, TDD and blood phosphorus were the key factors influencing the efficacy of Insulin pump. Among them, qualified blood glucose control was positively correlated with blood phosphorus, and negatively correlated with 2-hour postprandial insulin and TDD. CONCLUSION: CSII with insulin pump is an ideal method for short-term intensive treatment of type 2 diabetes. In order to achieve a more satisfactory rate of qualified blood glucose control, more attention should be paid to the patient's blood phosphorus, 2-hour postprandial insulin and TDD in clinical use.
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ObjectiveThis study aims to examine the effect of Rhei Radix et Rhizoma-Coptidis Rhizoma on reducing insulin resistance in db/db mice by regulating the adenylate activated protein kinase （AMPK）/UNC-51-like kinase 1 （ULK1）/key molecule of autophagy， benzyl chloride 1 （Beclin1） pathway and elucidate the underlying mechanism. MethodSixty 6-week-old male db/db mice were studied. They were randomly divided into the model group， metformin group （0.26 g·kg-1）， and low-， middle-， and high-dose groups （2.25， 4.5， 9 g·kg-1） of Rhei Radix et Rhizoma-Coptidis Rhizoma. A blank group of db/m mice of the same age was set， with 12 mice in each group. After eight weeks of continuous intragastric administration， the blank group and model group received distilled water intragastrically once a day. The survival status of the mice was observed， and fasting blood glucose （FBG） was measured using a Roche blood glucose device. Fasting serum insulin （FINS） was measured using an enzyme-linked immunosorbent assay， and the insulin resistance index （HOMA-IR） was calculated. Hematoxylin-eosin （HE） staining was performed to observe the pathological changes in the liver of the mice. The protein expression levels of AMPK， Beclin1， autophagy associated protein 5 （Atg5）， and p62 in liver tissue were determined by using Western blot. The protein expression levels of autophagy associated protein 1 light chain 3B （LC3B） and ULK1 in liver tissue were determined using immunofluorescence. Real-time fluorescence quantitative PCR （Real-time PCR） was used to measure mRNA expression levels of AMPK， Beclin1， Atg5， ULK1， and p62. ResultCompared with the blank group， the model group exhibited a significant increase in body mass （P<0.01）. Additionally， the levels of FBG， FINS， and HOMA-IR significantly changed （P<0.01）. The structure of liver cells was disordered. The protein expression levels of AMPK， Beclin1， and Atg5 in liver tissue were significantly decreased （P<0.01）， while the expression level of p62 protein was significantly increased （P<0.01）. The expression levels of mRNA and proteins were consistent. Compared with the model group， the body mass of the metformin group and high and medium-dose groups of Rhei Radix et Rhizoma-Coptidis Rhizoma was significantly decreased （P<0.05）. FBG， FINS， and HOMA-IR were significantly decreased （P<0.05，P<0.01）. After treatment， the liver structure damage in each group was alleviated to varying degrees. The protein expressions of AMPK， Beclin1， Atg5， LC3B， and ULK1 were increased （P<0.05，P<0.01）， while the protein expression of p62 was decreased （P<0.01）. The expression levels of mRNA and proteins were generally consistent. ConclusionThe combination of Rhei Radix et Rhizoma-Coptidis Rhizoma can effectively improve liver insulin resistance， regulate the AMPK autophagy signaling pathway， alleviate insulin resistance in db/db mice， and effectively prevent the occurrence and development of type 2 diabetes.
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Insulin resistance （IR） is an important pathological and physiological mechanism of type 2 diabetes （T2DM）， and the treatment of IR has become the key to the prevention and treatment of T2DM. IR is a state of insensitivity or reduced sensitivity of insulin-stimulated tissue cells to glucose， resulting in cells that are unable to efficiently take up glucose in the bloodstream and thus causing hyperglycemia. Adenosine monophosphate-activated protein kinase （AMPK） is an energy-sensing enzyme that can regulate multiple metabolic pathways and maintain the stability of adenosine triphosphate （ATP） in the cell. In recent years， traditional Chinese medicine （TCM） has played an increasingly important role in the prevention and treatment of T2DM. The research on exploring the AMPK signaling pathway of TCM intervention in the progress of T2DM has gradually increased. Many pharmacological studies have shown that TCM has advantages such as safety and high efficiency in the prevention and treatment of T2DM. AMPK signaling pathway is one of the key pathways for the active ingredients of TCM and TCM extracts to improve IR. Active ingredients such as phenols， flavonoids， polysaccharides， alkaloids， and saponins， as well as other herbal extracts can improve IR by activating the AMPK signaling pathway cascade response， thereby improving IR by regulating glucolipid metabolism， inhibiting inflammatory response， anti-oxidative stress and maintaining mitochondrial homeostasis. Based on this， this paper reviews the pharmacological and experimental research results of TCM intervening the AMPK signaling pathway to improve IR in recent years， expecting to provide reference for further research， development and application of TCM in intervening IR and treating T2DM.
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ObjectiveTo investigate the effect and mechanism of Shenqi Tangluo pill （SQTLP） on oxidative stress injury of skeletal muscle of type 2 diabetes mellitus （T2DM） mice based on nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1）/NAD（P）H quinone oxidoreductase 1 （NQO1） pathway. MethodA total of 60 7-week-old male db/db mice ［specific pathogen-free （SPF） grade］ were selected and fed for one week for adaption. They were divided into the model control group， SQTLP low-， medium- and high-dose （19， 38， and 76 g·kg-1） groups and metformin group （0.26 g·kg-1） by gavage. Each group consisted of 12 mice. Twelve male db/m mice of the same age were selected as the blank group. The intervention was implemented continuously for 8 weeks. Fasting blood glucose （FBG） was detected. Fasting serum insulin （FINS） levels were detected by enzyme-linked immunosorbent assay （ELISA）， and the homeostasis model assessment-insulin resistance （HOMA-IR） index and the homeostasis model assessment-insulin sensitivity index （HOMA-ISI） were calculated. Oral glucose tolerance test （OGTT） and insulin tolerance test （ITT） were conducted. The activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） and the contents of malondialdehyde （MDA） and reduced nicotinamide adenine dinucleotide phosphate （NADPH） in skeletal muscle tissues were detected by biochemical kits. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in skeletal muscle tissues. The levels of reactive oxygen species （ROS） and 4-hydroxynonenal （4-HNE） in skeletal muscle tissue were detected by immunofluorescence （IF）. The expression levels of Nrf2， HO-1， NQO1 and glutamate-cysteine ligase catalytic subunit （GCLC） proteins in skeletal muscle tissues were detected by Western blot. ResultCompared with those in the blank group， FBG， FINS and HOMA-IR in the model group were significantly increased （P<0.05）， while HOMA-ISI was decreased （P<0.05）. The results of OGTT and ITT showed that blood glucose was significantly increased at all time points （P<0.05）， and glucose tolerance and insulin tolerance were significantly impaired. SOD and GSH-Px activities in skeletal muscle tissues were significantly decreased （P<0.05）， and MDA and NADPH contents were significantly increased （P<0.05）. In skeletal muscle tissues， the arrangement of muscle fibers was loose， the nucleus was disordered， and inflammatory cells were infiltrated. The expression levels of ROS and 4-HNE in skeletal muscle tissues were significantly increased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly decreased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the metformin group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that blood glucose in the metformin group was significantly decreased at all time points （P<0.05）. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue of the metformin group. The expressions of ROS and 4-HNE in skeletal muscle tissues were decreased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly increased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the SQTLP medium- and high-dose groups were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the glucose tolerance and insulin tolerance of mice were improved in each dose group of SQTLP. The GSH-Px activity in the SQTLP low-dose group was significantly increased （P<0.05）， and the NADPH content was decreased （P<0.05）. The activities of SOD and GSH-Px in the SQTLP medium- and high-dose groups were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. The skeletal muscle tissue injury of mice in each dose group of SQTLP was ameliorated to different degrees. In the SQTLP medium- and high-dose groups， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05）. Compared with those in the SQTLP low-dose group， FBG and HOMA-IR in the SQTLP high-dose group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the SQTLP high-dose group significantly improved the glucose tolerance and insulin tolerance of mice. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05） in the skeletal muscle tissue of the SQTLP high-dose group. ConclusionSQTLP can significantly improve IR in T2DM mice， and the mechanism is related to SQTLP activating the Nrf2/HO-1/NQO1 signaling pathway， promoting the expression of antioxidant enzymes， and thus improving the oxidative stress injury in the skeletal muscle.
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ObjectiveTo investigate the therapeutic effect of Baihe Wuyaotang （BWT） on non-alcoholic fatty liver disease （NAFLD） and elucidate its underlying mechanism. MethodC57BL/6J mice were randomly assigned to six groups： normal control， model， positive drug （pioglitazone hydrochloride 1.95×10-3 g·kg-1）， and low-， medium-， and high-dose BWT （1.3，2.5 and 5.1 g·kg-1）. Following a 12-week high-fat diet （HFD） inducement， the mice underwent six weeks of therapeutic intervention with twice-daily drug administration. Body weight was monitored weekly throughout the treatment period. At the fifth week， glucose tolerance （GTT） and insulin tolerance （ITT） tests were conducted. Subsequently， the mice were euthanized for the collection of liver tissue and serum， and the subcutaneous adipose tissue （iWAT） and epididymal adipose tissue （eWAT） were weighed. Serum levels of total triglycerides （TG） and liver function indicators，such as alanine aminotransferase （ALT） and aspartate aminotransferase （AST）， were determined. Histological examinations， including oil red O staining， hematoxylin-eosin （HE） staining， Masson staining， and transmission electron microscopy， were performed to evaluate hepatic lipid deposition， pathological morphology， and ultrastructural changes， respectively. Meanwhile， Western blot and real-time quantitative polymerase chain reaction （Real-time PCR） were employed to analyze alterations， at both gene and protein levels， the insulin signaling pathway molecules， including insulin receptor substrate 1/2/protein kinase B/forkhead box gene O1 （IRS1/2/Akt/FoxO1）， glycogen synthesis enzymes phosphoenolpyruvate carboxy kinase （Pepck） and glucose-6-phosphatase （G6Pase）， lipid metabolism-related genes stearoyl-coA desaturase-1 （SCD-1） and carnitine palmitoyltransferase-1 （CPT-1）， fibrosis-associated molecules α-smooth muscle actin （α-SMA）， type Ⅰ collagen （CollagenⅠ）， and the fibrosis canonical signaling pathway transforming growth factor-β1/drosophila mothers against decapentaplegic protein2/3（TGF-β1/p-Smad/Smad2/3）， inflammatory factors such as interleukin（IL）-6， IL-8， IL-11， and IL-1β， autophagy markers LC3B Ⅱ/Ⅰ and p62/SQSTM1， and the expression of mammalian target of rapamycin （mTOR）. ResultCompared with the model group， BWT reduced the body weight and liver weight of NAFLD mice（P<0.05， P<0.01）， inhibited liver lipid accumulation， and reduced the weight of white fat： it reduced the weight of eWAT and iWAT（P<0.05， P<0.01） as well as the serum TG content（P<0.05， P<0.01）. BWT improved the liver function as reflected by the reduced ALT and AST content（P<0.05， P<0.01）. It improved liver insulin resistance by upregulating IRS2， p-Akt/Akt， p-FoxO1/FoxO1 expressions（P<0.05）. Besides， it improved glucose and lipid metabolism disorders： it reduced fasting blood glucose and postprandial blood glucose（P<0.05， P<0.01）， improved GTT and ITT（P<0.05， P<0.01）， reduced the expression of Pepck， G6Pase， and SCD-1（P<0.01）， and increased the expression of CPT-1（P<0.01）. The expressions of α-SMA， Collagen1， and TGF-β1 proteins were down-regulated（P<0.05， P<0.01）， while the expression of p-Smad/Smad2/3 was downregulated（P<0.05）， suggesting BWT reduced liver fibrosis. BWT inhibited inflammation-related factors as it reduced the gene expression of IL-6， IL-8， IL-11 and IL-1β（P<0.01） and it enhanced autophagy by upregulating LC3B Ⅱ/Ⅰ expression（P<0.05）while downregulating the expression of p62/SQSTM1 and mTOR（P<0.05）. ConclusionBWT ameliorates NAFLD by multifaceted improvements， including improving IR and glucose and lipid metabolism， anti-inflammation， anti-fibrosis， and enhancing autophagy. In particular， BWT may enhance liver autophagy by inhibiting the mTOR-mediated signaling pathway.
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Objective To explore the influencing factors of bone mineral density (BMD) in obese children in Qianjiang area and analyze the correlation between BMD and insulin resistance. Methods The data on pediatric cases from the outpatient department of Jianghan Oilfield General Hospital in Qianjiang from January 2018 to December 2022 were collected. A total of 183 obese children who met the inclusion and exclusion criteria were included in the study and selected in the observation group. A total of 352 children undergoing physical examination during the same period were selected as the control group. Results The body mass, waist circumference, waist to hip ratio, and BMI of obese children were significantly higher than those of the control group (P<0.001). Biochemical indexes including FBG, FINS, Home-IR, ALP, and LDL-C in obese children were significantly higher than those in the control group (P<0.05), while bone mineral density, Ca, P, sOC and HDL-C were significantly lower than those in the control group (P<0.001). The bone mineral density of obese children was significantly correlated with their exercise intensity, sunshine exposure duration, sitting time, intake of milk and dairy products, intake of sweets, supplementation of trace elements, BMI, Home-IR, and sex (all P<0.05). BMI, Home-IR, sex, exercise intensity, and sunshine exposure length were independent risk factors affecting bone mineral density of obese children (all P<0.05). Bone mineral density was negatively correlated with BMI and Home-IR (P=0.028 and0.017, respectively), and positive correlation with exercise intensity and sunlight exposure (P=0.033). Conclusion BMD of obese children in Qianjiang area is affected by gender, body mass index, diet, vitamin intake, and physical activity, and is negatively correlated with insulin resistance. Home-IR can be used as a reference for screening BMD of obese children.
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The correct pairing of disulfide bonds maintains the correct folding mode and high-level structure formation of peptides and protein drugs, which is crucial for the quality control of products. In order to ensure that the disulfide bonds are correctly paired, disulfide bond analysis is an essential part of peptides and protein drug characterization. Mass spectrometry can be used to analyze disulfide bonds. However, insulin and its analogues have two pairs of disulfide bonds without restriction enzyme cutting site. Conventional collision-induced dissociation (CID) and high-energy induced cleavage (HCD) cannot accurately locate the complex disulfide bond. In our study, three methods were used to localize the complex disulfide, including enzyme digestion combined with key peptide fragment in source decay (ISD) fragmentation method, enzyme digestion combined with partial reduction alkylation method, intact protein source ISD and electron transfer dissociation (ETD) cleavage method, The applicability of insulin aspart, insulin lispro and insulin glargine were also investigated. This study provides a new way for the quality control of disulfide bonding mode of insulin and its analogues, and also provides a reference for the disulfide bond localization of peptides or proteins containing this complex disulfide bond.
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OBJECTIVE To study the improvement effects of poria acid on insulin resistance in rats with polycystic ovary syndrome （PCOS） and its mechanism. METHODS One hundred and twenty-six female rats were randomly separated into blank group， PCOS group， poria acid low-dose group （8.33 mg/kg）， pachymic acid high-dose group （33.32 mg/kg）， ethinylestradiol cyproterone group （positive control group， 0.34 mg/kg）， recombinant rat high mobility group protein B1 protein （rHMGB1） group （8 μg/kg）， and poria acid high dose+rHMGB1 group （33.32 mg/kg poria acid+8 μg/kg rHMGB1）， with 18 rats in each group. Except for the blank group， the rats in all other groups were given Letrozole suspension intragastrically to construct the PCOS model. After successful modeling， administration was performed once a day for 4 weeks. After medication， the fasting blood glucose and fasting insulin levels， and insulin resistance index （HOMA-IR） were measured in rats； the levels of follicle-stimulating hormone （FSH）， luteinizing hormone （LH） and testosterone （T） in rat serum， and the levels of interleukin-1β （IL-1β） and tumor necrosis factor- α （TNF- α） in ovarian tissue were detected； ovarian coefficients of rats were calculated； the pathological changes of ovarian tissue were observed； the expressions of HMGB1， receptor for advanced glycosylation elaine_ tanghong@sina.com end product （RAGE） and phosphorylated nuclear factor κB p65 （p-NF-κB p65） proteins were determined in ovarian tissue of rats. RESULTS Compared with the blank group， the pathological injury of ovarian tissue of rats in the PCOS group was serious， the levels of fasting blood glucose and fasting insulin， HOMA-IR and ovarian coefficient were increased， the levels of serum LH and T were increased， while the levels of FSH were decreased； the levels of IL-1β and TNF-α， the expressions of HMGB1， RAGE and p-NF-κB p65 protein in ovarian tissue were increased， with statistical significance （P＜0.05）. Compared with the PCOS group， pathological damage of ovarian tissue was reduced in poria acid low-dose and high-dose groups and ethinylestradiol cyproterone group， and fasting blood glucose， fasting insulin levels， HOMA-IR and ovarian coefficient were decreased； serum LH and T levels were decreased， while FSH levels were increased； the levels of IL-1β and TNF-α and the expressions of HMGB1， RAGE and p-NF-κB p65 protein in ovarian tissue were decreased， with statistical significance （P＜0.05）. The trend of corresponding indexes in rHMGB1 group was opposite to the above （P＜0.05）. Compared with poria acid high-dose group， the changes of the above indexes were reversed significantly in poria acid high-dose+rHMGB1 group （P＜0.05）. CONCLUSIONS Poria acid may improve insulin resistance and inhibit inflammatory reaction in PCOS rats by inhibiting HMGB1/ RAGE pathway.
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ObjectiveTo observe the therapeutic effect of Qiwei Baizhusan（QWBZS） on diabetic encephalopathy（DE） rat model， and to explore the possible mechanism of QWBZS in the treatment of DE based on phosphatidylinositol 3-kinase（PI3K）/protein kinase B（Akt）/glycogen synthase kinase-3β（GSK-3β） signaling pathway. MethodForty-eight SPF male Wistar rats were randomly divided into blank group（8 rats） and high-fat diet group（40 rats）. After 12 weeks of feeding， rats in the high-fat diet group were intraperitoneally injected with 35 mg·kg-1 of 1% streptozotocin（STZ） for 2 consecutive days to construct a DE model， and rats in the blank group were injected with the same amount of sodium citrate buffer. After successful modeling， according to blood glucose and body weight， model rats were randomly divided into model group， low， medium and high dose groups of QWBZS（3.15， 6.3， 12.6 g·kg-1）， combined western medicine group（metformin+rosiglitazone， 0.21 g·kg-1）， with 6 rats in each group. The administration group was given the corresponding dose of drug by gavage， and the blank group and the model group were given an equal volume of 0.9% sodium chloride solution by gavage， 1 time/day for 6 weeks. Morris water maze was used to detect the spatial memory ability of DE rats. Fasting insulin （FINS） level was detected by enzyme-linked immunosorbent assay（ELISA） and insulin resistance index（HOMA-IR） was calculated. Hematoxylin-eosin（HE） staining was used to observe the morphological changes of hippocampus in rats， ELISA was used to detect the indexes of oxidative stress in hippocampal tissues， real-time fluorescence quantitative polymerase chain reaction（Real-time PCR） was used to detect mRNA expression levels of PI3K， Akt， nuclear transcription factor-κB（NF-κB）， tumor necrosis factor-α（TNF-α） and interleukin-1β（IL-1β） in hippocampus， and Western blot was used to detect the protein expression of PI3K， Akt， phosphorylated（p）-Akt， GSK-3β and p-GSK-3β in hippocampus of rats. ResultCompared with the blank group， FINS and HOMA-IR values of the model group were significantly increased（P<0.01）， the path of finding the original position of the platform was significantly increased， and the escape latency was significantly prolonged（P<0.01）， the morphology of neuronal cells in hippocampal tissues was disrupted， the levels of reactive oxygen species（ROS） and malondialdehyde（MDA） in hippocampus of rats were increased， and the activity of superoxide dismutase（SOD） was decreased（P<0.05， P<0.01）， mRNA expression levels of PI3K and Akt were decreased（P<0.01）， mRNA expression levels of NF-κB， TNF-α and IL-1β were increased（P<0.05， P<0.01）， the protein expression levels of PI3K， p-Akt and p-GSK-3β were significantly decreased， and the protein expression of GSK-3β was significantly increased（P<0.01）. Compared with the model group， the FINS and HOMA-IR values of the medium dose group of QWBZS and the combined western medicine group were significantly decreased（P<0.01）， the path of finding the original position of the platform and the escape latency were significantly shortened（P<0.01）， the hippocampal tissue structure of rats was gradually recovered， and the morphological damage of nerve cells was significantly improved， the contents of ROS and MDA in hippocampus of rats decreased and the level of SOD increased（P<0.01）， the mRNA expression levels of PI3K and Akt were increased（P<0.01）， and the mRNA expression levels of NF-κB， TNF-α and IL-1β were decreased （P<0.05， P<0.01）， the protein expression levels of PI3K， p-Akt and p-GSK-3β were significantly increased（P<0.01）， and the expression of GSK-3β was significantly decreased（P<0.01）. ConclusionQWBZS can alleviate insulin resistance in DE rats， it may repair hippocampal neuronal damage and improve learning and cognitive ability of DE rats by activating PI3K/Akt/GSK-3β signaling pathway.