Diabetes: insulin resistance and derangements in lipid metabolism. Cure through intervention in fat transport and storage

Alterations in nonesterified free fatty acid trafficking rather than hyperandrogenism contribute to metabolic health in obese women with polycystic ovary syndrome

OBJECTIVE

To determine whether alterations in nonesterified fatty acid (NEFA) dynamics or degree of hyperandrogenism (HA) contribute to the difference in insulin sensitivity between women with metabolically healthy obese polycystic ovary syndrome (PCOS) (MHO-PCOS) and women with metabolically unhealthy obese PCOS (MUO-PCOS).

DESIGN

Prospective cross-sectional study.

SETTING

Tertiary-care academic center.

PATIENTS

One hundred twenty-five obese women with PCOS.

INTERVENTION

Consecutive obese (body mass index [BMI] ≥ 30 kg/m2) oligo-ovulatory women (n = 125) with PCOS underwent an oral glucose tolerance test and a subgroup of 16 participants underwent a modified frequently sampled intravenous glucose tolerance test to determine insulin-glucose and -NEFA dynamics.

MAIN OUTCOME MEASURES

Degree of insulin resistance (IR) in adipose tissue (AT) basally (Adipo-IR) and dynamically (the nadir in NEFA levels observed [NEFAnadir], the time it took for NEFA levels to reach nadir [TIMEnadir], and the percent suppression in plasma NEFA levels from baseline to nadir [%NEFAsupp]); peak lipolysis rate (SNEFA) and peak rate of NEFA disposal from plasma pool (KNEFA); whole-body insulin-glucose interaction (acute response of insulin to glucose [AIRg], insulin sensitivity index [Si], glucose effectiveness [Sg], and disposition index [Di]); and HA (hirsutism score, total and free testosterone levels, and dehydroepiandrosterone sulfate levels).

RESULTS

A total of 85 (68%) women were MUO-PCOS and 40 (32%) were MHO-PCOS using the homeostasis model of assessment of IR. Subjects with MUO-PCOS and MHO-PCOS did not differ in mean age, BMI, waist-to-hip ratio, HA, and lipoprotein levels. By a modified frequently sampled intravenous glucose tolerance test, eight women with MUO-PCOS had lesser Si, KNEFA, and the percent suppression in plasma NEFA levels from baseline to nadir (%NEFAsupp) and greater TIMEnadir, NEFAnadir, and baseline adipose tissue IR index (Adipo-IR) than eight subjects with MHO-PCOS, but similar fasting NEFA levels and SNEFA. Women with MUO-PCOS had a higher homeostasis model of assessment-β% and fasting insulin levels than women with MHO-PCOS. In bivalent analysis, Si correlated strongly and negatively with Adipo-IR and NEFAnadir, weakly and negatively with TIMEnadir, and positively with KNEFA and %NEFAsupp, in women with MUO-PCOS only.

CONCLUSION

Independent of age and BMI, women with MUO-PCOS have reduced NEFA uptake and altered insulin-mediated NEFA suppression, but no difference in HA, compared with women with MHO-PCOS. Altered insulin-mediated NEFA suppression, rather than HA or lipolysis rate, contributes to variations in insulin sensitivity among obese women with PCOS.

A retrospective study investigating the clinical significance of body mass index in acute pancreatitis

Background

Acute pancreatitis is an unpredictable and potentially fatal condition for which no definitive cure is currently available. Our research focused on exploring the connection between body mass index, a frequently overlooked risk factor, and both the onset and progression of acute pancreatitis.

Material/Methods

A total of 247 patients with acute pancreatitis admitted to Jiangsu Provincial Hospital of Chinese Medicine from January 2021 to February 2023 were retrospectively reviewed. After screening, 117 patients with complete height and body weight data were selected for detailed assessment. Additionally, 85 individuals who underwent physical examinations at our hospital during this period were compiled to create a control group. The study received ethical approval from the ethics committee of Jiangsu Province Hospital of Chinese Medicine (Ref: No.2022NL-114-02) and was conducted in accordance with the China Good Clinical Practice in Research guidelines.

Results

A significant difference in body mass index (BMI) was observed between the healthy group and acute pancreatitis (AP) patients (p < 0.05), with a more pronounced disparity noted in cases of hyperlipidemic acute pancreatitis (p < 0.01). A potential risk for AP was identified at a BMI greater than 23.56 kg/m2 (AUC = 0.6086, p < 0.05). Being in the obese stage I (95%CI, [1.11-1.84]) or having a BMI below 25.4 kg/m2 (95%CI, [1.82-6.48]) are identified as risk factors for adverse AP progression. Moreover, BMI effectively predicts the onset of acute edematous pancreatitis and acute necrotizing pancreatitis (AUC = 0.7893, p < 0.001, cut-off value = 25.88 kg/m2). A higher BMI correlates with increased recurrence rates within a short timeframe (r = 0.7532, p < 0.01).

Conclusions

Elevated BMI is a risk factor for both the occurrence and progression of AP, and underweight status may similarly contribute to poor disease outcomes. BMI is crucial for risk prediction and stratification in AP and warrants ongoing monitoring and consideration.

Role of Bioactive Compounds, Novel Drug Delivery Systems, and Polyherbal Formulations in the Management of Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is an autoimmune disorder that generally causes joint synovial inflammation as well as gradual cartilage and degenerative changes, resulting in progressive immobility. Cartilage destruction induces synovial inflammation, including synovial cell hyperplasia, increased synovial fluid, and synovial pane development. This phenomenon causes articular cartilage damage and joint alkalosis. Traditional medicinal system exerts their effect through several cellular mechanisms, including inhibition of inflammatory mediators, oxidative stress suppression, cartilage degradation inhibition, increasing antioxidants and decreasing rheumatic biomarkers. The medicinal plants have yielded a variety of active constituents from various chemical categories, including alkaloids, triterpenoids, steroids, glycosides, volatile oils, flavonoids, lignans, coumarins, terpenes, sesquiterpene lactones, anthocyanins, and anthraquinones. This review sheds light on the utilization of medicinal plants in the treatment of RA. It explains various phytoconstituents present in medicinal plants and their mechanism of action against RA. It also briefs about the uses of polyherbal formulations (PHF), which are currently in the market and the toxicity associated with the use of medicinal plants and PHF, along with the limitations and research gaps in the field of PHF. This review paper is an attempt to understand various mechanistic approaches employed by several medicinal plants, their possible drug delivery systems and synergistic effects for curing RA with minimum side effects.

Diabetes noninvasive diagnostics and monitoring through volatile biomarkers analysis in the exhaled breath using optical absorption spectroscopy

The review is aimed on the analysis the abilities of noninvasive diagnostics and monitoring of diabetes mellitus (DM) and DM-associated complications through volatile molecular biomarkers detection in the exhaled breath. The specific biochemical reactions in the body of DM patients and their associations with volatile molecular biomarkers in the breath are considered. The applications of optical spectroscopy methods, including UV, IR, and terahertz spectroscopy for DM-associated volatile molecular biomarkers measurements, are described. The applications of similar technique combined with machine learning methods in DM diagnostics using the profile of DM-associated volatile molecular biomarkers in exhaled air or "pattern-recognition" approach are discussed.

Effect of nano-encapsulated food flavorings on streptozotocin-induced diabetic rats

Flavors and aromas are widely used in food and pharmaceutical industries to enhance food palatability. However, it is worth noting that they may also have bioactivity. This study aims to examine the potential impact of key flavors and their nanocapsules on health and diseases, such as type 2 diabetes mellitus (T2DM). The 36 nanocapsules of key flavorings were prepared by high shear homogenization (HSH). Seventy-two male Sprague-Dawley rats received a single dosage of streptozotocin (35 mg kg-1 body weight) intraperitoneally. All of the nutritional and biochemical parameters were statistically analyzed. A virtual docking study was conducted. Linalool nanoemulsion results showed the highest encapsulation efficiency (86.76%), while isoamyl acetate nanoparticles showed the lowest (69.99%). According to GC-MS analysis, encapsulation did not affect the flavoring structure with particle size distributions ranging from 277.3 to 628.8 nm. Using TEM, nanoemulsion particles appeared spherical with a desired nanometric diameter size. In the oral glucose tolerance test, flavorings in oil and nanoforms had no discernible hypoglycemia effects in normal rats. The nutritional and biochemical parameters confirmed that both normal and nanoencapsulation forms demonstrated a potential anti-hyperglycemic effect, and enhanced the rat health compared to the raw flavorings. The studied flavorings and their nanocapsules seem to have the potential double effect of a flavor compound as a food palatability enhancer with a potential beneficial effect on type 2 diabetes mellitus without any health drawbacks.

Role of dysfunctional peri-organ adipose tissue in metabolic disease

Metabolic disease is a complex disorder defined by a group with interrelated factors. There is growing evidence that obesity can lead to a variety of metabolic diseases, including diabetes and cardiovascular disease. Excessive adipose tissue (AT) deposition and ectopic accumulation can lead to increased peri-organ AT thickness. Dysregulation of peri-organ (perivascular, perirenal, and epicardial) AT is strongly associated with metabolic disease and its complications. The mechanisms include secretion of cytokines, activation of immunocytes, infiltration of inflammatory cells, involvement of stromal cells, and abnormal miRNA expression. This review discusses the associations and mechanisms by which various types of peri-organ AT affect metabolic diseases while addressing it as a potential future treatment strategy.

Relationship between testosterone-estradiol ratio and some anthropometric and metabolic parameters among Nigerian men

Background

Alterations in sex hormone levels are implicated in the regulation of metabolic processes in men. In recent years, the prevalence of metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes, has risen in Nigeria. In men, these disorders may be associated with the ratio of serum testosterone to estradiol levels. Therefore, we investigated the relationship between the testosterone-estradiol (T/E2) ratio, anthropometry, and metabolic parameters in Nigerian men.

Method

Eighty-five adult men were recruited for this study. Participants' data such as age, weight, height, BMI, and waist circumference were collected. Plasma total testosterone and estradiol levels, as well as metabolic parameters such as fasting blood sugar, creatinine, urea, HDL cholesterol, total cholesterol, and triglycerides levels, were determined. The data were analyzed using SPSS version 25 software.

Results

Anthropometric parameters such as weight, height, BMI, and waist circumference showed a negative correlation with plasma T/E2 (r = -0.265, -0.288, -0.106, -0.204; p = 0.007, 0.004, 0.167, 0.061 respectively). However, the T/E2 ratio showed a positive correlation with the metabolic parameters such as fasting blood sugar, HDL cholesterol levels, plasma creatinine, and urea (r = 0.219, 0.096, 0.992, 0.152; p = 0.022, 0.192, <0.001, 0.082 respectively), while there were negative correlations with total cholesterol and triglycerides levels (r = -0.200, -0.083; p = 0.034, 0.226 respectively).

Conclusion

These findings show that there are significant correlations between the T/E2 ratio and weight, height, fasting blood sugar, creatinine, and urea, while there are no significant correlations between T/E2 ratio and BMI, waist circumference, HDL-cholesterol, and triglycerides.

Chemical derivatization strategy for mass spectrometry-based lipidomics

Lipids, serving as the structural components of cellular membranes, energy storage, and signaling molecules, play the essential and multiple roles in biological functions of mammals. Mass spectrometry (MS) is widely accepted as the first choice for lipid analysis, offering good performance in sensitivity, accuracy, and structural characterization. However, the untargeted qualitative profiling and absolute quantitation of lipids are still challenged by great structural diversity and high structural similarity. In recent decade, chemical derivatization mainly targeting carboxyl group and carbon-carbon double bond of lipids have been developed for lipidomic analysis with diverse advantages: (i) offering more characteristic structural information; (ii) improving the analytical performance, including chromatographic separation and MS sensitivity; (iii) providing one-to-one chemical isotope labeling internal standards based on the isotope derivatization regent in quantitative analysis. Moreover, the chemical derivatization strategy has shown great potential in combination with ion mobility mass spectrometry and ambient mass spectrometry. Herein, we summarized the current states and advances in chemical derivatization-assisted MS techniques for lipidomic analysis, and their strengths and challenges are also given. In summary, the chemical derivatization-based lipidomic approach has become a promising and reliable technique for the analysis of lipidome in complex biological samples.

Long-term association of pericardial adipose tissue with incident diabetes and prediabetes: the Coronary Artery Risk Development in Young Adults Study

OBJECTIVES

We examined whether pericardial adipose tissue (PAT) is predictive of prediabetes and type 2 diabetes over time.

METHODS

In total, 2,570 adults without prediabetes/diabetes from the Coronary Artery Risk Development in Young Adults Study were followed up over 15 years. PAT volume was measured by computed tomography scans, and the new onset of prediabetes/diabetes was examined 5 years, 10 years, and 15 years after the PAT measurements. Multivariable Cox regression models were used to examine the association between the tertile of PAT and incident prediabetes/diabetes up to 15 years later. The predictive ability of PAT (vs. waist circumference [WC], body mass index [BMI], waist-to-height ratio [WHtR]) for prediabetes/diabetes was examined by comparing the area under the receiver operating characteristic curve (AUC).

RESULTS

The highest tertile of PAT was associated with a 1.56 times (95% confidence interval [CI], 1.03 to 2.34) higher rate of diabetes than the lowest tertile; however, no association was found between the highest tertile of PAT and prediabetes in the fully adjusted models, including additional adjustment for BMI or WC. In the fully adjusted models, the AUCs of WC, BMI, WHtR, and PAT for predicting diabetes were not significantly different, whereas the AUC of WC for predicting prediabetes was higher than that of PAT.

CONCLUSIONS

PAT may be a significant predictor of hyperglycemia, but this association might depend on the effect of BMI or WC. Additional work is warranted to examine whether novel adiposity indicators can suggest advanced and optimal information to supplement the established diagnosis for prediabetes/diabetes.

Therapeutic significance of thymoquinone-loaded chitosan nanoparticles on streptozotocin/nicotinamide-induced diabetic rats: In vitro and in vivo functional analysis

To overcome the low bioavailability of lipophilic free thymoquinone (TQ), this study aims to evaluate a novel oral formula of TQ-loaded chitosan nanoparticles (TQ-CsNPs) for the effective treatment of diabetes. The XRD, FTIR, FESEM, HRTEM, and dynamic light scattering were all conducted on the prepared formula. The release pattern of TQ, cytotoxicity against MRC-5 cell line (human lung fibroblast cells), and antidiabetic activity on streptozotocin/nicotinamide (STZ/NA) rat model of diabetes were investigated. The results confirmed the formation of TQ-CsNPs with an entrapment efficiency of 75.7 ± 6.52 %, a mean Zetasizer distribution of 84.25 nm, and an average particle size of about 50 nm. After 24 h, the percentage of free TQ-cumulative release was approximately 35.8 %, whereas TQ-CsNPs showed a sustained release pattern of 78.5 %. The investigated formula was not toxic to normal lung cells, and more efficient in ameliorating the altered glycemia, dyslipidemia, inflammation, and oxidative stress induced by STZ/NA than free TQ, blank CsNPs, and metformin-HCl (as a reference drug). Additionally, TQ-CsNPs restored the normal pancreatic islets' configuration and morphometry, suggesting a potent insulinotropic action. In conclusion, the antidiabetic efficacy of TQ was improved by engaging TQ with CsNPs as an excellent nanoplatform to enhance the oral bioavailability of TQ.

Body weight and fat mass across the menopausal transition: hormonal modulators

BACKGROUND

The role of the menopause in weight gain is an understudied yet important field, given the rising prevalence of obesity and its associated risk of disease.

OBJECTIVE

To review the current evidence regarding the impact of the menopausal transition on changes in body composition and fat accrual in women and the hormonal mechanisms underlying the process.

METHODS

A critical appraisal of the current literature by experts in the field.

RESULTS

Menopause is associated with an overall increase in fat mass, which tends to accumulate around the waist. There is also a decrease in lean mass, particularly evident in the lower limbs. Reduced energy expenditure (EE) has been confirmed in parallel with increased food intake, the latter being more evident in experimental models. A prominent role has been found for the estrogen receptor (ER) alpha isoform in fat accrual. Human studies suggest a role for androgens in central fat accumulation and type 2 diabetes. FSH is a key factor in the process of fat accumulation, but only in rodents. Clinical studies suggest that these endocrine alterations are insufficient to explain the observed changes.

CONCLUSIONS

The menopausal transition is associated with an increase in adiposity, which accumulates preferentially in the abdominal area. Hypoestrogenism and the imbalance of the androgen/estrogen ratio are strong candidates to explain the phenomenon, although other hormonal factors probably also play a role. The impact on risk of disease is still insufficiently known, although an association with risk factors, such as an unfavorable lipid profile or insulin resistance seems likely.

Lipid accumulation product (LAP) as a potential index to predict risk of insulin resistance in young, non-obese Asian Indian males from Southern India: observations from hyperinsulinemic-euglycemic clamp studies

INTRODUCTION

We aimed to compare the predictive accuracy of surrogate indices namely the lipid accumulation product (LAP) index, homeostatic model of assessment of insulin resistance (HOMA-IR), fasting glucose-insulin ratio (FG-IR) and the quantitative-insulin sensitivity check index (QUICKI), against the M value of hyperinsulinemic-euglycemic clamp (HEC), and to determine a cut-off value for the LAP index to predict risk of insulin resistance in non-obese (body mass index <21 kg/m²), normoglycemic, Asian Indian males from Southern India.

RESEARCH DESIGN AND METHODS

Data of HEC studies performed in 108 non-obese, normoglycemic, Asian Indian males was obtained retrospectively and the M value (a measure of whole-body insulin sensitivity) was calculated. The M value is the rate of whole-body glucose metabolism at the hyperinsulinemic plateau (a measure of insulin sensitivity) and is calculated between 60 and 120 min after the start of the insulin infusion in the HEC procedure. The LAP index, the HOMA-IR, FG-IR and QUICKI were calculated. Spearman's correlation and logistic regression analysis were performed. Cut-off value for the LAP index was obtained using receiver operating characteristics with area under curve (AUC) analysis at 95% CI. P value <0.05 was considered to be statistically significant.

RESULTS

Significant negative correlation was observed for the M value with LAP index (r=-0.39, p<0.001) while significant positive correlation was noted with FG-IR (r=0.25; p<0.01) and QUICKI (r=0.22; p<0.01). The LAP index cut-off value ≥33.4 showed 75% sensitivity and 75% specificity with AUC (0.72) to predict risk of insulin resistance in this cohort.

CONCLUSION

The LAP index showed higher predictive accuracy for the risk of insulin resistance as compared with HOMA-IR, QUICKI and FG-IR in non-obese, normoglycemic Asian Indian males from Southern India.

Serum non-esterified fatty acid levels and hip fracture risk: The Cardiovascular Health Study

Among elderly participants from the Cardiovascular Health Study, we found that non-esterified trans fatty acid levels had a significant prospective association with hip fracture risk. Other non-esterified fatty acid classes were not associated with hip fracture risk.

INTRODUCTION

Serum non-esterified fatty acids (NEFAs) are bioactive metabolic intermediates that can be taken up by bone tissue. Their associations with hip fracture risk have not been previously examined.

METHODS

Thirty-five individual NEFAs in five classes (saturated [SFA], mono-un-saturated [MUFA], poly-unsaturated n-6 and n-3 [PUFA], and trans-FA) were measured in Cardiovascular Health Study participants (n = 2139, mean age 77.8 years) without known diabetes. The multivariable associations of NEFA levels with hip fracture risk were evaluated in Cox hazards models.

RESULTS

We documented 303 incident hip fractures during 11.1 years of follow-up. Among the five NEFA classes, total trans FA levels were positively associated with higher hip fracture risk (HR 1.17 [95% CI, 1.04, 1.31; p = 0.01] per one standard deviation higher level). The SFA lignoceric acid (24:0) was positively associated with higher risk (HR 1.09 [1.04, 1.1]; p < 0.001), while behenic (22:0) and docosatetraenoic (22:4 n6) acids were associated with lower risk (HR 0.76 [0.61, 0.94]; p = 0.01; 0.84 [0.70, 1.00]; p = 0.05, respectively).

CONCLUSION

Total plasma trans NEFA levels are related to hip fracture risk, suggesting an unrecognized benefit of their systematic removal from food. Novel associations of individual NEFAs with hip fracture risk require confirmation in other cohort studies.

miR-344-5p Modulates Cholesterol-Induced β-Cell Apoptosis and Dysfunction Through Regulating Caveolin-1 Expression

Diabetes is a metabolic disorder induced by the modulation of insulin on glucose metabolism, and the dysfunction and decreased number of islets β-cells are the main causes of T2DM (type 2 diabetes mellitus). Among multiple factors that might participate in T2DM pathogenesis, the critical roles of miRNAs in T2DM and β-cell dysfunction have been reported. Through bioinformatics analyses and literature review, we found that miR-344 might play a role in the occurrence and progression of diabetes in rats. The expression levels of miR-344-5p were dramatically decreased within cholesterol-stimulated and palmitic acid (PA)-induced rats' islet β-cells. In cholesterol-stimulated and PA-induced diabetic β-cell model, cholesterol-caused and PA-caused suppression on cell viability, increase in intracellular cholesterol level, decrease in GSIS, and increase in lip droplet deposition were dramatically attenuated via the overexpression of miR-344-5p, whereas aggravated via the inhibition of miR-344-5p. miR-344-5p also inhibited cholesterol-induced β-cell death via affecting the apoptotic caspase 3/Bax signaling. Insulin receptor downstream MPAK/ERK signaling was involved in the protection of miR-344-5p against cholesterol-induced pancreatic β-cell dysfunction. Moreover, miR-344-5p directly targeted Cav1; Cav1 silencing could partially reverse the functions of miR-344-5p inhibition upon cholesterol-induced β-cell dysfunction, β-cell apoptosis, the apoptotic caspase 3/Bax signaling, and insulin receptor downstream MPAK/ERK signaling. In conclusion, the miR-344-5p/Cav1 axis modulates cholesterol-induced β-cell apoptosis and dysfunction. The apoptotic caspase 3/Bax signaling and MAPK/ERK signaling might be involved.

Insulin Action, Glucose Homeostasis and Free Fatty Acid Metabolism: Insights From a Novel Model

Glucose and free fatty acids (FFA) are essential nutrients that are both partly regulated by insulin. Impaired insulin secretion and insulin resistance are hallmarks of aberrant glucose disposal, and type 2 diabetes (T2DM). In the current study, a novel model of FFA kinetics is proposed to estimate the role insulin action on FFA lipolysis and oxidation allowing estimation of adipose tissue insulin sensitivity (S_IFFA ). Twenty-five normal volunteers were recruited for the current study. To participate, volunteers had to be less than 40 years of age and have a body mass index (BMI) < 30 kg/m², and be free of medical comorbidity. The proposed model of FFA kinetics was used to analyze the data derived from the insulin-modified FSIGT. Mean fractional standard deviations of the parameter estimates were all less than 20%. Standardized residuals of the fit of the model to the FFA temporal data were randomly distributed, with only one estimated point lying outside the 2-standard deviation range, suggesting an acceptable fit of the model to the FFA data. The current study describes a novel one-compartment non-linear model of FFA kinetics during an FSIGT that provides an FFA metabolism insulin sensitivity parameter (S_IFFA ). Furthermore, the models suggest a new role of glucose as the modulator of FFA disposal. Estimates of S_IFFA confirmed previous findings that FFA metabolism is more sensitive to changes in insulin than glucose metabolism. Novel derived indices of insulin sensitivity of FFA (S_IFFA ) were correlated with minimal model indices. These associations suggest a cooperative rather than competitive interplay between the two primary nutrients (glucose and FFA) and allude to the FFA acting as the buffer, such that glucose homeostasis is maintained.

Sleep-Disordered Breathing and Free Fatty Acid Metabolism

BACKGROUND

Sleep-disordered breathing (SDB) is independently associated with insulin resistance, glucose intolerance, and type 2 diabetes mellitus. However, data on whether SDB alters the metabolism of free fatty acids (FFAs) are lacking.

RESEARCH QUESTION

The primary objective of the current study was to characterize alterations in FFA metabolism across the spectrum of SDB severity.

STUDY DESIGN AND METHODS

The study sample included 118 participants with and without SDB who underwent full-montage polysomnography, the frequently sampled IV glucose tolerance test (FSIGTT), and body composition measurements including determination of percent body fat. Parameters of lipolysis suppression, time to FFA nadir, and FFA rebound after an IV glucose challenge were derived using a mathematical model. Multivariable regression analyses were used to characterize the independent associations between SDB severity and parameters of FFA metabolism.

RESULTS

SDB severity, as assessed by the apnea-hypopnea index, was associated with adipocyte insulin resistance, a decrease in the glucose- and insulin-mediated suppression of lipolysis, a longer duration to reach a nadir in FFA levels during the FSIGTT, and a sluggish rebound in FFA levels after suppression. Severity of SDB-related hypoxemia was independently associated with adipocyte insulin resistance and the time to reach the FFA nadir during the FSIGTT. Finally, a higher percentage of stage N3 sleep was positively associated with greater suppression of lipolysis and a faster rebound in the FFA levels during the FSIGTT.

INTERPRETATION

Independent of adiposity, SDB is associated with impairments in FFA metabolism, which may contribute to the development of glucose intolerance and type 2 diabetes in SDB.

Chemical profile changes during pile fermentation of Qingzhuan tea affect inhibition of α-amylase and lipase

Qingzhuan tea (QZT), a post-fermented tea, has been reported to have anti-obesity and anti-hyperglycemic effects, perhaps due to bioactive compounds that inhibit lipase and α-amylase. It is unknown what chemical constituents’ changes and what bioactive compounds occur during the manufacture of QZT. The aim of this study was to determine the secondary metabolites changes that occur during post-fermentation and how these changes affect the ability of QZT to inhibit the activities of lipase and α-amylase. During the processing steps, metabolites levels and their inhibitory effects on lipase and α-amylase were assessed. Changes in content and activities suggested that the first turn over or the second turn over was critical for the formation and conversion of bioactive compounds responsible for the anti-obesity and hypoglycemic effects. The relationship between constituents and activities was further evaluated by correlation analysis, which showed that amino acids and flavonoids might be responsible for the anti-obesity and anti-hyperglycemic effects of QZT. This study clarified that compounds were altered during pile fermentation of QZT and tentatively identified the bioactive compounds formed during QZT manufacture.

Effects of Propolis Extract and Propolis-Derived Compounds on Obesity and Diabetes: Knowledge from Cellular and Animal Models

Propolis is a natural product resulting from the mixing of bee secretions with botanical exudates. Since propolis is rich in flavonoids and cinnamic acid derivatives, the application of propolis extracts has been tried in therapies against cancer, inflammation, and metabolic diseases. As metabolic diseases develop relatively slowly in patients, the therapeutic effects of propolis in humans should be evaluated over long periods of time. Moreover, several factors such as medical history, genetic inheritance, and living environment should be taken into consideration in human studies. Animal models, especially mice and rats, have some advantages, as genetic and microbiological variables can be controlled. On the other hand, cellular models allow the investigation of detailed molecular events evoked by propolis and derivative compounds. Taking advantage of animal and cellular models, accumulating evidence suggests that propolis extracts have therapeutic effects on obesity by controlling adipogenesis, adipokine secretion, food intake, and energy expenditure. Studies in animal and cellular models have also indicated that propolis modulates oxidative stress, the accumulation of advanced glycation end products (AGEs), and adipose tissue inflammation, all of which contribute to insulin resistance or defects in insulin secretion. Consequently, propolis treatment may mitigate diabetic complications such as nephropathy, retinopathy, foot ulcers, and non-alcoholic fatty liver disease. This review describes the beneficial effects of propolis on metabolic disorders.

The Protective Role of Calbindin-D9k on Endoplasmic Reticulum Stress-Induced Beta Cell Death

Intracellular calcium ion content is tightly regulated for the maintenance of cellular functions and cell survival. Calbindin-D_9k (CaBP-9k) is responsible for regulating the distribution of cytosolic free-calcium ions. In this study, we aimed to investigate the effect of CaBP-9k on cell survival in pancreatic beta cells. Six-month-old wildtype CaBP-9k, CaBP-28k, and CaBP-9k/28k knockout (KO) mice were used to compare the pathological phenotypes of calcium-binding protein-deleted mice. Subsequently, the endoplasmic reticulum (ER) stress reducer tauroursodeoxycholic acid (TUDCA) was administered to wildtype and CaBP-9k KO mice. In vitro assessment of the role of CaBP-9k was performed following CaBP-9k overexpression and treatment with the ER stress inducer thapsigargin. Six-month-old CaBP-9k KO mice showed reduced islet volume and up-regulation of cell death markers resulting from ER stress, which led to pancreatic beta cell death. TUDCA treatment recovered islet volume, serum insulin level, and abdominal fat storage by CaBP-9k ablation. CaBP-9k overexpression elevated insulin secretion and recovered thapsigargin-induced ER stress in the INS-1E cell line. The results of this study show that CaBP-9k can protect pancreatic beta cell survival from ER stress and contribute to glucose homeostasis, which can reduce the risk of type 1 diabetes and provide the molecular basis for calcium supplementation to diabetic patients.

Future perspectives of the pharmacological management of diabetic dyslipidemia

INTRODUCTION

Diabetic dyslipidemia is frequent among patients with type 2 diabetes mellitus (T2DM) and is characterized by an increase in triglycerides (TGs), low-density lipoprotein cholesterol (LDL-C), and small-dense (atherogenic) particles, and by a decrease in low high-density lipoprotein cholesterol (HDL-C) and apolipoprotein (Apo) A1 that are strongly related to insulin resistance. The increased flux of free fatty acids from adipose tissue to the liver aggravates hepatic insulin resistance and promotes all of aspects of the dyslipidemic state. Areas covered: Statins are the first-line agents for treatment while other lipid-lowering drugs (ezetimibe, fibrate and proprotein convertase subtilisin/kexin type 9) or novel anti-diabetic agents (dipeptidyl peptidase-4 inhibitors (DPP-4is), glucagon like peptide-1 receptor agonist (GLP-1RA), sodium/glucose cotransporter 2 inhibitors (SGLT2is)) or nutraceuticals (berberine, omega 3 fatty acid, red yeast rice) can be used alone or in combination. Expert commentary: In patients with T2DM, lipid abnormalities should be identified and treated as part of the overall diabetic treatment, in order to prevent cardiovascular disease. The choice of drugs to be used is mainly based on the lipid profile and on the characteristic lipoprotein abnormalities; the use of new drugs for the treatment of hyperglycemia and lipids alteration in these patients can improve diabetic dyslipidemia.

Effects of citral on oxidative stress and hepatic key enzymes of glucose metabolism in streptozotocin/high-fat-diet induced diabetic dyslipidemic rats

OBJECTIVES

Phytochemicals such as polyphenols, alkaloids, and terpenoids, protect against the development of early stages and complications of diabetes mellitus according to various reports. The aim of this study was to measure the anti-dyslipidemic and anti-diabetic effects of Citral on high-fat-diet (HFD) and streptozotocin (STZ) induced diabetic dyslipidemic rats and to see also its effect on carbohydrate metabolic regulatory enzymes in the liver.

MATERIALS AND METHODS

Rats were kept on a high-fat diet for 2 weeks, then diabetes was induced by a single dose of STZ (35 mg/kg/BW, intraperitoneally), Citral was administered orally at a dose of 45 mg/kg/BW for 28 days to diabetic rats. Blood glucose, plasma insulin, and lipid profile in blood were studied. Antioxidant activities were assayed in the liver, pancreas, and adipose tissues. Carbohydrate metabolic enzymes of the liver were also studied in diabetic dyslipidemic rats.

RESULTS

The results of this study confirmed that administration of Citral significantly (P<0.05) decreased the blood glucose level and increased plasma insulin in diabetic rats. Citral also improved oxidative markers along with anti-oxidative enzymes of the liver, adipose tissue, and pancreas in the HFD/STZ group. Citral also regulated the activity of the glucose-metabolic enzymes in the liver. The results of the present study were compared to Glibenclamide, which is a standard oral drug for lowering the blood sugar.

CONCLUSION

Results may show that Citral possesses anti-dyslipidemic activity as well as anti-diabetic activity and also regulates the enzyme activity of glycolytic and gluconeogenic processes in the liver.

Runx1 Role in Epithelial and Cancer Cell Proliferation Implicates Lipid Metabolism and Scd1 and Soat1 Activity

The role of lipid metabolism in epithelial stem cell (SC) function and carcinogenesis is poorly understood. The transcription factor Runx1 is known to regulate proliferation in mouse epithelial hair follicle (HF) SCs in vivo and in several mouse and human epithelial cancers. We found a novel subset of in vivo Runx1 HFSC target genes related to lipid metabolism and demonstrated changes in distinct classes of lipids driven by Runx1. Inhibition of lipid-enzymes Scd1 and Soat1 activity synergistically reduces proliferation of mouse skin epithelial cells and of human skin and oral squamous cell carcinoma cultured lines. Varying Runx1 levels induces changes in skin monounsaturated fatty acids (e.g., oleate, a product of Scd1) as shown by our lipidome analysis. Furthermore, varying Runx1 levels, the inhibition of Scd1, or the addition of Scd1-product oleate, individually affects the plasma membrane organization (or fluidity) in mouse keratinocytes. These factors also affect the strength of signal transduction through the membranes for Wnt, a pathway that promotes epithelial (cancer) cell proliferation and HFSC activation. Our working model is that HFSC factor Runx1 modulates the fatty acid production, which affects membrane organization, facilitating signal transduction for rapid proliferation of normal and cancer epithelial cells. Stem Cells 2018;36:1603-1616.

Medium-Chain Triglycerides Lower Blood Lipids and Body Weight in Streptozotocin-Induced Type 2 Diabetes Rats

Medium-chain triglycerides (MCTs) are distinguished from other triglycerides in that each fat molecule consists of 6 to 12 carbons in length. MCTs and long-chain triglycerides (LCTs) are absorbed and utilized in different ways. The aim of this study was to assess the effects of replacing soybean oil with MCT oil, in a low- or high-fat diet, on lipid metabolism in rats with streptozotocin-induced type 2 diabetes mellitus (T2DM). There were, thirty-two T2DM Sprague-Dawley rats divided into low-fat-soybean oil (LS), low-fat-MCT oil (LM), high-fat-soybean oil (HS), and high-fat-MCT oil (HM) groups. After 8 weeks, blood sugar, serum lipids, liver lipids, and enzyme activities related to lipid metabolism were measured. Under a high-fat diet condition, replacement of soybean oil with MCT oil lowered serum low-density lipoprotein cholesterol (LDL-C), non-esterified fatty acids, and liver total cholesterol; whilst it increased serum high-density lipoprotein cholesterol (HDL-C) and the HDL-C/LDL-C ratio. A low-fat diet with MCT oil resulted in lower body weight and reproductive white adipose tissues compared to the HS groups, and higher hepatic acyl-CoA oxidase activities (the key enzyme in the peroxisomal beta-oxidation) compared to the LS group in T2DM rats. In conclusion, MCTs showed more protective effects on cardiovascular health in T2DM rats fed a high-fat diet, by improving serum lipid profiles and reducing hepatic total cholesterol.

Metabolomics applied to the discovery of tuberculosis and diabetes mellitus biomarkers

Tuberculosis (TB) and diabetes mellitus Type 2 (DM2) are two diseases as ancient as they are harmful to human health. The outcome for both diseases in part depends on immune and metabolic individual responses. DM2 is increasing yearly, mainly due to environmental, genetic and lifestyle habits. There are multiple evidence that DM2 is one of the most important risk factor of becoming infected with TB or reactivating latent TB. Mass spectrometry-based metabolomics is an important tool for elucidating the metabolites and metabolic pathways that influence the immune responses to M. tuberculosis infection during diabetes. We provide an up-to-date review highlighting the importance and benefit of metabolomics for identifying biomarkers as candidate molecules for diagnosis, disease activity or prognosis.

Effects of Resveratrol and Mangiferin on PPARγ and FALDH Gene Expressions in Adipose Tissue of Streptozotocin-Nicotinamide-Induced Diabetes in Rats

Type 2 diabetes (T2D) is characterized by insufficient insulin secretion by the pancreatic beta cells and insulin resistance in liver, skeletal muscle, and white adipose tissue. Adipose tissue plays a major role in glucose homeostasis and lipid metabolism. Dietary antioxidants such as resveratrol and mangiferin may offer some protection against the early stage of diabetes mellitus. Therefore, an attempt has been made to investigate the effects of resveratrol and mangiferin on biochemical parameters and molecular mechanism of PPARγ and FALDH gene expression in adipose tissue of streptozotocin- (STZ-) nicotinamide- (NA-) induced diabetic rats. Albino Wister rats were randomly divided into five groups: control rats (Group 1), diabetic control rats (Group 2), diabetic rats given resveratrol (40 mg/kg body weight per day; Group 3), diabetic rats given mangiferin (40 mg/kg body weight per day; Group 4), diabetic rats given glibenclamide (0.6 mg/kg body weight per day; Group 5). Serum biochemical parameters-total cholesterol (TC), total triglyceride (TG), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, glycosylated hemoglobin (HbA1c), urea, and uric acid were analyzed. We found that the oral administration of resveratrol and mangiferin to STZ-NA-induced diabetic rats for 30 days showed the significant protective effect on all the biochemical parameters. A significant reduction in blood glucose and HbA1c levels was observed in rats treated with 40 mg/kg body weight per day of resveratrol or mangiferin. Moreover, both these antioxidants showed significant enhancement of PPARγ and FALDH gene expression in rat adipose tissue compared to control rats.

Comparisons of cardioprotective efficacy between fibroblast growth factor 21 and dipeptidyl peptidase-4 inhibitor in prediabetic rats

AIMS

Comparative efficacy between fibroblast growth factor 21 (FGF21) and vildagliptin on metabolic regulation, cardiac mitochondrial function, heart rate variability (HRV), and left ventricular (LV) function is not known. We hypothesized that FGF21 and vildagliptin share a similar efficacy in improving these parameters in high fat diet (HFD)-induced obese-insulin resistant rats.

METHODS

Twenty-four male Wistar rats were fed with either a normal diet (ND) or a HFD for 12 weeks. Then, ND rats were received vehicle (NDV). Rats in the HFD group were divided into three subgroups to receive either vehicle (HFV), recombinant human FGF21 (rhFGF21, 0.1 mg/kg/d, ip; HFF), or vildagliptin (3 mg/kg/d, PO; HFVil) for 28 days.

RESULTS

HFV rats developed obese-insulin resistance, increased serum tumor necrosis factors alpha (TNF-α) level, impaired heart rate variability (HRV) together with cardiac mitochondrial dysfunction, and LV dysfunction. Cardiac apoptosis was markedly increased in HFV rats indicated by decreased B-cell lymphoma 2 (Bcl-2) with increased Bcl2-associated X-protein (Bax) and cleaved caspase 3 expression. Cardiac FGF21 signaling pathways were markedly decreased in HFV rats indicated by decreased phosphor-fibroblast growth factor receptors 1 (p-FGFR1), phosphor-extracellular signal-regulated protein kinases 1 (p-ERK1/2), proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), and carnitine palmitoyltransferase-1 (CPT-1) expression. Although both FGF21 and vildagliptin similarly attenuated these impairments, only HFF rats had decreased body weight, visceral fat, and serum TNF-α levels.

CONCLUSIONS

FGF21 exerts better metabolic regulation and inflammation reduction than vildagliptin. However, FGF21 and vildagliptin shared a similar efficacy for cardioprotection by improving HRV and LV function.

Screening of stationary phase selectivities for global lipid profiling by ultrahigh performance supercritical fluid chromatography

The performance of seven sub-2-μm particle packed columns (2-picolylamine, 2-PIC; charged surface hybrid fluoro-phenyl, CSH-FP; high strength silica C18 SB, HSS-C₁₈; diethylamine, DEA; 1-aminoanthracene, 1-AA; high density diol and ethylene bridged hybrid; BEH) was examined for lipid separation in ultra-high performance supercritical fluid chromatography (UHPSFC) coupled to quadrupole time-of-flight mass spectrometry. Based on the results of the column screening a method for profiling of multiple lipid species from the major lipid classes was developed. Stationary phases containing β-hydroxy amines, i.e. 1-AA, DEA and 2-PIC, yielded strong retention and poor peak shapes of zwitterionic lipids with primary amine groups, such as phosphatidylserines, phosphatidylethanolamines and its lyso forms. The BEH and HSS-C₁₈ columns showed strong retention of polar and nonpolar lipids, respectively. The Diol column retained the majority of major lipid classes and also produced symmetric peaks. In addition, this column also produced the highest resolution within and between major lipid classes. An injection solvent composed of methanol:chloroform (1:2, v:v) and the addition of 20 mM ammonium formate in the mobile phase improved chromatographic separation and mass spectrometry detection in comparison to ammonium acetate or absence of additive. Finally, chromatographic and mass spectrometric parameters were optimized for the Diol column using a design of experiments approach. The separation mechanism on the Diol column depended on the lipid functionality and the length and degree of unsaturation of the acyl groups. The developed method could resolve 18 lipid classes and multiple lipids within each class, from blood serum and brain tissue in 11 min.

The Effects of Diet on the Proportion of Intramuscular Fat in Human Muscle: A Systematic Review and Meta-analysis

Background

There is an increasing trend in the consumption of poor-quality diets worldwide, contributing to the increase of non-communicable diseases. Diet directly influences physiological composition and subsequently physical health. Studies have shown that dietary macronutrient and energy content can influence the proportion of intramuscular fat (IMF), which mediates various metabolic and endocrine dysfunction. The purpose of this systematic review was to identify evidence in the literature assessing the association between different dietary interventions on the proportion of IMF in humans.

Methods

Three medical databases were investigated (Medline, EMBASE, and Cochrane) to identify studies assessing changes in IMF after dietary interventions. The primary outcome measure was the change in IMF proportions after a dietary intervention. The effects of high-fat, high-carbohydrate, low-calorie, and starvation diets were assessed qualitatively. A meta-analysis assessing the effect of high-fat diets was conducted. Follow-up sensitivity and subgroup analyses were also conducted.

Results

One thousand eight hundred and sixty-six articles were identified for review. Of these articles, 13 were eligible for inclusion after a full screening. High-fat diets increased IMF proportions, standardized mean difference = 1.24 (95% confidence interval, 0.43–2.05) and a significant overall effect size (P = 0.003). Diets with an increased proportion of carbohydrates decreased IMF proportions; however, increasing caloric intake with carbohydrates increased IMF. Starvation diets increased IMF stores, and hypocaloric diets did not result in any IMF proportion changes.

Conclusion

This systematic review suggests that high-fat diets and diets with caloric intake increased above the amount required to maintain BMI with carbohydrates, and short-term starvation diets are associated with increases in IMF content. Further studies are needed to assess the effects of macronutrient combinations on IMF and the influence of diet-induced IMF alterations on health outcomes. In addition, IMF poses a possibly effective clinical marker of health.

Chinese Olive (Canarium album L.) Fruit Extract Attenuates Metabolic Dysfunction in Diabetic Rats

Hyperglycemia and dysregulation of lipid metabolism play a crucial role in metabolic dysfunction. The aims of present study were to evaluate the ameliorative effect of the ethyl acetate fraction of Chinese olive fruit extract (CO-EtOAc) on high-fat diet (HFD) and streptozotocin (STZ)-induced diabetic rats. CO-EtOAc, rich in gallic acid and ellagic acid, could markedly decreased the body weight and epididymal adipose mass. In addition, CO-EtOAc increased serum HDL-C levels, hepatic GSH levels, and antioxidant enzyme activities; lowered blood glucose, serum levels of total cholesterol (TC), triglycerides (TG), bile acid, and tumor necrosis factor alpha (TNFα); and reduced TC and TG in liver. We further demonstrated that CO-EtOAc mildly suppressed hepatic levels of phosphorylated IRS-1, TNF-α, and IL-6, but enhanced Akt phosphorylation. The possible mechanisms of cholesterol metabolism were assessed by determining the expression of genes involved in cholesterol transportation, biosynthesis, and degradation. It was found that CO-EtOAc not only inhibited mRNA levels of SREBP-2, HMG-CoAR, SR-B1, and CYP7A1 but also increased the expression of genes, such as ABCA1 and LDLR that governed cholesterol efflux and cholesterol uptake. Moreover, the protein expressions of ABCA1 and LDLR were also significantly increased in the liver of rats supplemented with CO-EtOAc. We suggest that Chinese olive fruit may ameliorate metabolic dysfunction in diabetic rats under HFD challenge.

Treatment of diabetic mice with the SGLT2 inhibitor TA-1887 antagonizes diabetic cachexia and decreases mortality

A favorable effect of an inhibitor of the sodium–glucose cotransporter 2 (SGLT2i) on mortality of diabetic patients was recently reported, although mechanisms underlying that effect remained unclear. Here, we examine SGLT2i effects on survival of diabetic mice and assess factors underlying these outcomes. To examine SGLT2i treatment effects in a model of severe diabetes, we fed genetically diabetic db/db mice a high-fat diet and then assessed outcomes including diabetic complications between SGLT2i TA-1887-treated and control mice. We also compare effects of SGLT2i TA-1887 with those of lowering blood glucose levels via insulin treatment. Untreated db/db mice showed remarkable weight loss, or cachexia, while TA-1887-treated mice did not but rather continued to gain weight at later time points and decreased mortality. TA-1887 treatment prevented pancreatic beta cell death, enhanced preservation of beta cell mass and endogenous insulin secretion, and increased insulin sensitivity. Moreover, TA-1887 treatment attenuated inflammation, oxidative stress, and cellular senescence, especially in visceral white adipose tissue, and antagonized endothelial dysfunction. Insulin treatment of db/db mice also prevented weight loss and antagonized inflammation and oxidative stress. However, insulin treatment had less potent effects on survival and prevention of cellular senescence and endothelial dysfunction than did TA-1887 treatment. SGLT2i treatment prevents diabetic cachexia and death by preserving function of beta cells and insulin target organs and attenuating complications. SGLT2i treatment may be a promising therapeutic strategy for type 2 diabetes patients with morbid obesity and severe insulin resistance.

Sodium-glucose cotransporter 2 inhibitor (SGLT2i) has a favorable effect on mortality of diabetic subjects, but the mechanism stays unclear. Taichi Sugizaki at Kumamoto University examined SGLT2i effects in severe diabetic obese mice, and discovered that they showed prolonged survival without pathological weight loss, or cachexia. As with SGLT2i, Insulin also prevented cachexia, improved pancreatic beta cell function, insulin sensitivity and some organ damages. However, what makes SGLT2i important was to suppress cellular aging or vessel inflammation, while insulin accelerated those developments, which may lead to a result that SGLT2i has contributed to prolonged survival more than insulin. SGLT2i demonstrates an association with survival period upon maintaining good condition of pancreatic beta cells and insulin target organs, providing insight into strategies for treatment of severe diabetes.

The ratio of pericardial to subcutaneous adipose tissues is associated with insulin resistance

OBJECTIVE

To examine the association between pericardial adipose tissue (PAT) and the ratio of PAT to subcutaneous adipose tissue (SAT) with insulin resistance in adults with and without type 1 diabetes (T1D).

METHODS

Data for this report came from a substudy of the Coronary Artery Calcification in Type 1 Diabetes cohort (n = 83; 38 with T1D, 45 without T1D). Insulin resistance was measured by hyperinsulinemic-euglycemic clamp. Abdominal computed tomography (CT) was used to measure visceral adipose tissue (VAT) and SAT. PAT was measured from CT scans of the heart.

RESULTS

PAT and the ratio of PAT to SAT was higher in males compared to females. After adjustment for demographics, diabetes, blood pressure and lipid factors, BMI, VAT, and log PAT/SAT ratio, log PAT was positively associated with the glucose infusion rate (GIR) in females only (β = 3.36 ± 1.96, P = 0.097, P for sex interaction = 0.055). Conversely, the log PAT/SAT ratio was significantly associated with decreased GIR in both males and females (β = -2.08 ± 1.03, P = 0.047, P for sex interaction = 0.768).

CONCLUSIONS

A significant association between the PAT/SAT ratio and insulin resistance was found, independent of BMI, VAT, and PAT. These results highlight the importance of considering fat distribution independent of volume.

MicroRNAs and metabolic disorders - where are we heading?

MicroRNAs (miRNAs, miRs) are short, non-coding molecules engaged in normal functioning of eukaryotic cells, as negative regulators of gene expression. Since the first discovery of miRNA in the early 1990s, hundreds of different miRNAs and their targets have been identified. A growing number of studies have aimed to search for microRNAs which have a key role in the regulation of insulin signaling and metabolic homeostasis. Recent evidence indicates that dysregulation of miRNA expression is involved in the development of various diseases, including type 2 diabetes mellitus (T2DM), obesity and cardiovascular diseases. This review summarizes the biogenesis of miRNAs and their role in pancreatic β cell biology, insulin signaling and metabolism. We also discuss recent findings of miRNAs associated with metabolic disorders and vascular diabetic complications, their diagnosis and therapeutic value. The PubMed database and published reference lists were searched for articles published between 1990 and 2016 using the following keywords: miRNA, miRNA and pancreas; miRNA and insulin; miRNA and type 2 diabetes mellitus, miRNA and obesity, and miRNA and microvascular or macrovascular diabetic complication. This review indicates that miRNA functioning is significantly different in metabolic diseases than in the normal condition.

Higher pericardial adiposity is associated with prevalent diabetes: The Coronary Artery Risk Development in Young Adults study

BACKGROUND AND AIMS

Pericardial adipose tissue (PAT) is located on both sides of the pericardium. We tested whether PAT was associated with prevalent diabetes at the year 25 exam of the Coronary Artery Risk Development in Young Adults (CARDIA) study.

METHODS AND RESULTS

The CARDIA Year 25 exam (2010-2011) included complete data for all covariates on 3107 participants. Prevalent diabetes (n = 436) was defined as high fasting (≥126 mg/dl) or 2-h postload glucose (≥200 mg/dl) or HbA1c (≥6.5%) or use of diabetes medications. Volume of PAT was measured from computed tomographic scans. Logistic regression was performed to examine the relationship between quartiles of PAT and diabetes. In regression models adjusted for field center, sex, race, age, systolic blood pressure, total cholesterol, log triglycerides, and treatment with blood pressure and cholesterol lowering medication, PAT volume in the 4th quartile was significantly associated with diabetes status after adjustment for BMI (OR 2.57, 95% CI 1.66, 3.98) or visceral adipose tissue (OR 2.08, 95% CI 1.32, 3.29). PAT volume in the 2nd and 3rd quartiles was not significantly associated with diabetes status relative to the first quartile.

CONCLUSIONS

Metabolically active pericardial adipose tissue is associated with prevalent diabetes only at higher volumes independent of overall obesity.

Mini-review: diabetic renal complications, a potential stinky remedy

Chronic kidney disease is associated with vasculitis and is also an independent risk factor for peripheral vascular and coronary artery disease in diabetic patients. Despite optimal management, a significant number of patients progress toward end-stage renal disease (ESRD), a suggestion that the disease mechanism is far from clear. A reduction in hydrogen sulfide (H2S) has been suggested to play a vital role in diabetic vascular complications including diabetic nephropathy (DN). This mini-review highlights the recent findings on the role of H2S in mitigating abnormal extracellular matrix metabolism in DN. A discussion on the development of the newer slow-releasing H2S compounds and its therapeutic potential is also included.

An Overview of Murine High Fat Diet as a Model for Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a worldwide epidemic, which by all predictions will only increase. To help in combating the devastating array of phenotypes associated with T2DM a highly reproducible and human disease-similar mouse model is required for researchers. The current options are genetic manipulations to cause T2DM symptoms or diet induced obesity and T2DM symptoms. These methods to model human T2DM have their benefits and their detractions. As far as modeling the majority of T2DM cases, HFD establishes the proper etiological, pathological, and treatment options. A limitation of HFD is that it requires months of feeding to achieve the full spectrum of T2DM symptoms and no standard protocol has been established. This paper will attempt to rectify the last limitation and argue for a standard group of HFD protocols and standard analysis procedures.

Genes, Genetics, and Environment in Type 2 Diabetes: Implication in Personalized Medicine

Type 2 diabetes (T2D) is a multifactorial anomaly involving 57 genes located on 16 different chromosomes and 136 single nucleotide polymorphisms (SNPs). Ten genes are located on chromosome 1, followed by seven genes on chromosome 11 and six genes on chromosomes 3. Remaining chromosomes harbor two to five genes. Significantly, chromosomes 13, 14, 16, 18, 21, 22, X, and Y do not have any associated diabetogenic gene. Genetic components have their own pathways encompassing insulin secretion, resistance, signaling, and β-cell dysfunction. Environmental factors include epigenetic changes, nutrition, intrauterine surroundings, and obesity. In addition, ethnicity plays a role in conferring susceptibility to T2D. This scenario poses a challenge toward the development of biomarker for quick disease diagnosis or for generating a consensus to delineate different categories of T2D patients. We believe, before prescribing a generic drug, detailed genotypic information with the background of ethnicity and environmental factors may be taken into consideration. This nonconventional approach is envisaged to be more robust in the context of personalized medicine and perhaps would cause lot less burden on the patient ensuring better management of T2D.

The non-glycosylated isoform of MIC26 is a constituent of the mammalian MICOS complex and promotes formation of crista junctions

Mitochondrial membrane architecture is important for organelle function. Alterations thereof are linked to a number of human disorders including diabetes and cardiomyopathy. The MICOS complex was recently reported to be a central player determining cristae structure and formation of crista junctions. Here we investigated the functional role of MIC26, a lipoprotein formerly termed APOO. Its levels are increased in diabetic heart tissue and in blood plasma of patients suffering from acute coronary syndrome. We demonstrate that human MIC26 exists in three distinct forms: (1) a glycosylated and secreted 55kDa protein, (2) an ER/Golgi-resident form thereof, and (3) a non-glycosylated 22kDa mitochondrial protein. The latter isoform spans the mitochondrial inner membrane and physically interacts with several MICOS complex subunits such as MIC60, MIC27, and MIC10. We further demonstrate that MIC26 and MIC27, a homologous protein formerly termed APOOL, regulate their levels in an antagonistic manner. Both proteins are positively correlated with the levels of MIC10 as well as tafazzin, an enzyme required for cardiolipin remodeling. Overexpression of MIC26 induced fragmentation of mitochondria, promoted ROS formation and resulted in impaired mitochondrial respiration. Downregulation of MIC26 induced a decrease in mitochondrial oxygen consumption, whereas mitochondrial network morphology and ROS levels remained unaffected. MIC26 depletion led to alterations in mitochondrial ultrastructure and caused a significant reduction in the number of crista junctions. In summary, we show that the human apolipoprotein MIC26 is a bona fide subunit of the MICOS complex and that MIC26 is linked to cardiolipin metabolism and promotes crista junction formation.

Medicinal plants with potential anti-arthritic activity

ETHNO PHARMACOLOGICAL RELEVANCE

Traditional medicinal plants are practiced worldwide for treatment of arthritis especially in developing countries where resources are meager. This review presents the plants profiles inhabiting throughout the world regarding their traditional usage by various tribes/ethnic groups for treatment of arthritis.

MATERIALS AND METHODS

Bibliographic investigation was carried out by analyzing classical text books and peer reviewed papers, consulting worldwide accepted scientific databases from the last six decades. Plants/their parts/extracts/polyherbal formulations, toxicity studies for arthritis have been included in the review article. The profiles presented also include information about the scientific name, family, dose, methodology along with mechanism of action and toxicity profile. Research status of 20 potential plant species has been discussed. Further, geographical distribution of research, plants distribution according to families has been given in graphical form.

RESULTS

485 plant species belonging to 100 families, traditionally used in arthritis are used. Among 100 plant families, malvaceae constitute 16, leguminasae 7, fabaceae 13, euphorbiaceae 7, compositae 20, araceae 7, solanaceae 12, liliaceae 9, apocynaceae, lauraceae, and rubiaceae 10, and remaining in lesser proportion. It was observed in our study that majority of researches are carried mainly in developing countries like India, China, Korea and Nigeria.

CONCLUSION

This review clearly indicates that list of medicinal plants presented in this review might be useful to researchers as well as practioners. This review can be useful for preliminary screening of potential anti-arthritis plants. Further toxicity profile given in the review can be useful for the researchers for finding the safe dose.

Vagus nerve contributes to metabolic syndrome in high-fat diet-fed young and adult rats

NEW FINDINGS

What is the central question of this study? Different nerve contributes periods of life are known for their differential sensitivity to interventions, and increased parasympathetic activity affects the development and maintenance of obesity. Thus, we evaluated the involvement of the vagus nerve by performing a vagotomy in young or adult rats that were offered an obesogenic high-fat diet. What is the main finding and its importance? Although the accumulation of adipose tissue decreased in both younger and older groups, the younger rats showed a greater response to the effects of vagotomy in general. In addition to the important role of the parasympathetic activity, we suggest that the vagus nerve contributes to the condition of obesity. Obesity has become a global problem, and this condition develops primarily because of an imbalance between energy intake and expenditure. The high complexity involved in the regulation of energy metabolism results from several factors besides endocrine factors. It has been suggested that obesity could be caused by an imbalance in the autonomous nervous system, which could lead to a condition of high parasympathetic activity in counterpart to low sympathetic tonus. High-fat (HF) diets have been used to induce obesity in experimental animals, and their use in animals leads to insulin resistance, hyperinsulinaemia and high parasympathetic activity, among other disorders. The aim of this work was to evaluate the effects of a vagotomy performed at the initiation of a HF diet at two different stages of life, weaning and adulthood. The vagotomy reduced parasympathetic activity (-32 and -51% in normal fat-fed rats and -43 and -55% in HF diet-fed rats; P < 0.05) and fat depots (-17 and -33%, only in HF diet-fed rats; P < 0.05). High-fat diet-fed rats exhibited fasting hyperinsulinaemia (fivefold higher in young rats and threefold higher in older rats; P < 0.05); however, vagotomy corrected it in younger rats only, and a similar effect was also observed during the glucose tolerance test. The insulin resistance exhibited by the HF diet-fed groups was not altered in the vagotomized rats. We suggest that the vagus nerve, in addition to the important role of parasympathetic activity, contributes to the condition of obesity, and that non-vagal pathways may be involved along with the imbalanced autonomic nervous system.

Effect of Hypericum perforatum L. extract on insulin resistance and lipid metabolic disorder in high-fat-diet induced obese mice

Natural product Hypericum perforatum L. has been used in folk medicine to improve mental performance. However, the effect of H. perforatum L. on metabolism is still unknown. In order to test whether H. perforatum L. extract (EHP) has an effect on metabolic syndrome, we treated diet induced obese (DIO) C57BL/6J mice with the extract. The chemical characters of EHP were investigated with thin-layer chromatography, ultraviolet, high-performance liquid chromatography (HPLC), and HPLC-mass spectrometry fingerprint analysis. Oral glucose tolerance test (OGTT), insulin tolerance test (ITT), and the glucose infusion rate (GIR) in hyperinsulinemic–euglycemic clamp test were performed to evaluate the glucose metabolism and insulin sensitivity. Skeletal muscle was examined for lipid metabolism. The results suggest that EHP can significantly improve the glucose and lipid metabolism in DIO mice. In vitro, EHP inhibited the catalytic activity of recombinant human protein tyrosine phosphatase 1B (PTP1B) and reduced the protein and mRNA levels of PTP1B in the skeletal muscle. Moreover, expressions of genes related to fatty acid uptake and oxidation were changed by EHP in the skeletal muscle. These results suggest that EHP may improve insulin resistance and lipid metabolism in DIO mice. © 2014 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd.

Effects of daily consumption of synbiotic bread on insulin metabolism and serum high-sensitivity C-reactive protein among diabetic patients: a double-blind, randomized, controlled clinical trial

BACKGROUND

This study was conducted to evaluate the effects of daily consumption of synbiotic bread on the metabolic status of patients with type 2 diabetes mellitus.

METHODS

This randomized, double-blind, controlled clinical trial was performed in 81 diabetic patients. The subjects were randomly assigned to consumption of synbiotic (n = 27), probiotic (n = 27), or control bread (n = 27) for 8 weeks 3 times a day in a 40-gram package. The synbiotic bread contained Lactobacillus sporogenes (1 × 10(8) CFU) and 0.07 g inulin per 1 g. The probiotic bread contained L. sporogenes (1 × 10(8) CFU per 1 g). Fasting blood samples were taken at baseline and after an 8-week intervention for quantification of related factors.

RESULTS

Consumption of the synbiotic bread resulted in a significant reduction in serum insulin levels (-3.2 ± 5.4 vs. -0.3 ± 3.4 and 0.6 ± 4.7 µIU/ml, respectively, p = 0.007), homeostatic model assessment for insulin resistance scores (-1.5 ± 2.7 vs. -0.2 ± 1.6 and 0.4 ± 3.5, respectively, p = 0.03), and homeostatic model assessment-β-cell function (-7.2 ± 16.3 vs. -0.7 ± 10.8 and 0.7 ± 8.2, respectively, p = 0.04) compared to the probiotic and control breads. We did not find any significant effect of synbiotic bread consumption on fasting plasma glucose, the quantitative insulin sensitivity check index, or serum hs-CRP levels compared to other breads.

CONCLUSION

Consumption of the synbiotic bread among diabetic patients had beneficial effects on insulin metabolism.