Serotonin improves glucose metabolism by Serotonylation of the small GTPase Rab4 in L6 skeletal muscle cells

Effectiveness of a nurse-led management intervention on systolic blood pressure among type 2 diabetes patients in Uganda: a cluster randomized trial

BACKGROUND

Hypertension (HT) is an orchestrator of atherosclerotic cardiovascular disease (ASCVD) in people living with type 2 diabetes (T2D). Control of systolic blood pressure (SBP) and HT as a whole is suboptimal in diabetes, partly due to the scarcity of doctors. While nurse-led interventions are pragmatic and cost-effective in the control of HT in primary health care, their effectiveness on SBP control among patients with T2D in Uganda is scantly known.

AIM

We evaluated the effectiveness of a nurse-led management intervention on SBP among T2D patients with a high ASCVD risk in Uganda.

METHODS

A two-armed cluster randomized controlled trial compared the nurse-led management intervention with usual doctor-led care. The intervention involved training nurses to provide structured health education, protocol-based HT/CVD management, 24-h phone calls, and 2-monthly text messages for 6 months. The primary outcome was the mean difference in SBP change among patients with T2D with a high ASCVD risk in the intervention and control groups after 6 months. The secondary outcome was the absolute difference in the number of patients at target for SBP, total cholesterol (TC), fasting blood glucose (FBG), glycated hemoglobin (HbA1C), low-density lipoprotein (LDL), triglycerides (TG), and body mass index (BMI) after the intervention. The study was analyzed according to the intention-to-treat principle. Generalized estimating equations were used to assess intra-cluster effect modifiers. Statistical significance was set at 0.05 for all analyses.

RESULTS

Eight clinics (n = 388 patients) were included (intervention 4 clinics; n = 192; control 4 clinics; n = 196). A nurse-led intervention reduced SBP by -11.21 ± 16.02 mmHg with a mean difference between the groups of -13.75 mmHg (95% CI -16.48 to -11.02, p < 0.001). An increase in SBP of 2.54 ± 10.95 mmHg was observed in the control group. Diastolic blood pressure was reduced by -6.80 ± 9.48 mmHg with a mean difference between groups of -7.20 mmHg (95% C1 -8.87 to -5.48, p < 0.001). The mean differences in the change in ASCVD score and glycated hemoglobin were -4.73% (95% CI -5.95 to -3.51, p = 0.006) and -0.82% (95% CI -1.30 to -0.35, p = 0.001), respectively. There were significant absolute differences in the number of patients at target in SBP (p = 0.001), DBP (p = 0.003), and TC (p = 0.008).

CONCLUSION

A nurse-led management intervention reduces SBP and ASCVD risk among patients with T2D. Such an intervention may be pragmatic in the screening and management of HT/ASCVD in Uganda.

TRIAL REGISTRATION

Pan African Clinical Trial Registry, PACTR202001916873358, registered on 6th October 2019.

The janus face of serotonin: Regenerative promoter and chronic liver disease aggravator

The progression of liver diseases, from viral hepatitis and fatty liver disease to cirrhosis and hepatocellular carcinoma (HCC), is the most representative series of pathological events in liver diseases. While serotonin (5-HT) primarily regulates brain functions such as psychology, mood, and appetite in the central nervous system (CNS), peripheral 5-HT plays a crucial role in regulating tumor development, glucose and lipid metabolism, immune function and inflammatory response related to liver diseases. These peripheral physiological processes involving 5-HT are the key mechanisms driving the development of these liver diseases. This study presents an overview of the existing literature, focusing on the role of 5-HT in HCC, cirrhosis, fatty liver disease, viral hepatitis, and liver injury. In summary, while 5-HT promotes liver regeneration, it can also contribute to the progression of chronic liver disease. These findings indicate the potential for the development and use of 5-HT-related drugs for the treatment of liver diseases, including HCC and cirrhosis.

Role of Serotonylation and SERT Posttranslational Modifications in Alzheimer's Disease Pathogenesis

The neurotransmitter serotonin (5-hydroxytryptamine, 5-HT) is implicated mainly in Alzheimer's disease (AD) and reported to be responsible for several processes and roles in the human body, such as regulating sleep, food intake, sexual behavior, anxiety, and drug abuse. It is synthesized from the amino acid tryptophan. Serotonin also functions as a signal between neurons to mature, survive, and differentiate. It plays a crucial role in neuronal plasticity, including cell migration and cell contact formation. Various psychiatric disorders, such as depression, schizophrenia, autism, and Alzheimer's disease, have been linked to an increase in serotonin-dependent signaling during the development of the nervous system. Recent studies have found 5-HT and other monoamines embedded in the nuclei of various cells, including immune cells, the peritoneal mast, and the adrenal medulla. Evidence suggests these monoamines to be involved in widespread intracellular regulation by posttranslational modifications (PTMs) of proteins. Serotonylation is the calcium-dependent process in which 5-HT forms a long-lasting covalent bond to small cytoplasmic G-proteins by endogenous transglutaminase 2 (TGM2). Serotonylation plays a role in various biological processes. The purpose of our article is to summarize historical developments and recent advances in serotonin research and serotonylation in depression, aging, AD, and other age-related neurological diseases. We also discussed several of the latest developments with Serotonin, including biological functions, pathophysiological implications and therapeutic strategies to treat patients with depression, dementia, and other age-related conditions.

Differences in the Impact of Various Types of Exercise on Irisin Levels: A Systematic Review and Meta-Analysis

Background

Irisin, a myokine that is responsive to exercise, induces significant changes in subcutaneous adipose tissue. By promoting the browning of white fat tissue, it enhances energy expenditure, thereby addressing overweight and obesity. This systematic review and meta-analysis aimed to compare the effects of different types of physical exercises on irisin levels in overweight and obese adults.

Methods

Specifically, the review focused on studies involving obese or overweight individuals who participated in exercise training for a minimum of 8 weeks, with measured and reported changes in serum irisin levels compared to a control group. Data were collected from four databases (Google Scholar, ISI Web of Science Core Collection, PubMed, and Scopus). The risk of bias was assessed using the Begg and Egger tests, and the results were synthesized.

Results

Initial searches identified 560 titles, out of which only seven met the criteria for inclusion in the systematic review. Statistical analysis demonstrated a significant increase in serum irisin concentration (SMD = 0.957, P = 0.005) among obese and overweight individuals who engaged in exercise, compared to the passive control group. High-intensity interval training (HIIT) (SMD = 1.229, P < 0.001) had a more pronounced effect on increasing serum irisin levels than other exercise protocols. Furthermore, the effectiveness of exercise varied based on the participants' weight status (significant changes for overweight individuals; P < 0.001 and insignificant changes for obese individuals; P = 0.1), age (significant changes for those under 40 years old; P < 0.001 and insignificant changes for those over 40 years old; P = 0.322), and gender (significant changes for men; P < 0.001 and insignificant changes for women; P = 0.285).

Conclusions

Consequently, exercise can elevate serum irisin levels, leading to alterations in adipose tissue phenotype and thermogenesis, ultimately contributing to weight reduction in obese and overweight individuals.

Tissue transglutaminase: a multifunctional and multisite regulator in health and disease

Tissue transglutaminase (TG2) is a widely distributed multifunctional protein involved in a broad range of cellular and metabolic functions carried out in a variety of cellular compartments. In addition to transamidation, TG2 also functions as a Gα signaling protein, a protein disulfide isomerase (PDI), a protein kinase, and a scaffolding protein. In the nucleus, TG2 modifies histones and transcription factors. The PDI function catalyzes the trimerization and activation of heat shock factor-1 in the nucleus and regulates the oxidation state of several mitochondrial complexes. Cytosolic TG2 modifies proteins by the addition of serotonin or other primary amines and in this way affects cell signaling. Modification of protein-bound glutamines reduces ubiquitin-dependent proteasomal degradation. At the cell membrane, TG2 is associated with G protein-coupled receptors (GPCRs), where it functions in transmembrane signaling. TG2 is also found in the extracellular space, where it functions in protein cross-linking and extracellular matrix stabilization. Of particular importance in transglutaminase research are recent findings concerning the role of TG2 in gene expression, protein homeostasis, cell signaling, autoimmunity, inflammation, and hypoxia. Thus, TG2 performs a multitude of functions in multiple cellular compartments, making it one of the most versatile cellular proteins. Additional evidence links TG2 with multiple human diseases including preeclampsia, hypertension, cardiovascular disease, organ fibrosis, cancer, neurodegenerative diseases, and celiac disease. In conclusion, TG2 provides a multifunctional and multisite response to physiological stress.

Adaptation and psychometric assessment of the instrument "Partners of Adults with Type 1 Diabetes Distress Scale" in a Brazilian population

Objectives

To adapt the instrument "Partners of Adults with Type 1 Diabetes Distress Scale" (Partner-DDS) into Brazilian culture, and to evaluate the psychometric characteristics of the adapted version.

Methods

All the cultural adaptation steps of the measure's instruments were followed. The psychometric properties such as reliability (stability by test-retest; internal consistency), and convergent construct validity were performed.

Results

Of all 72 partners, 69.4% were male, mean age: 42.69 ± 14.09 years, mean of marriage duration: 14.74 ± 12.41 years, and mean schooling: 11.81 ± 3.91 years.The internal consistency of the instrument (Cronbach Alpha) was 0.90. The intra-class coefficient (stability) was 0.80 (0.72-0.84). The Spearman coefficient (convergent construct validity) between the Partner-DDS scale and the Anxiety subscale of the Hospital Anxiety and Depression Scale (HADS-A) was 0.4273 (p < 0.0002).

Conclusions

The steps of the instruments' cultural adaptation were appropriately performed. The Brazilian version of the Partner- DDS scale demonstrates reliable psychometric properties for being used in POPWT1D distress evaluation in Brazil.

Innovation

The cultural adaptation of Partner-DDS scale into Brazilian Portuguese is a helpful innovation to assess the emotional burden in POPWT1D. This tool could be used to provide education and psychological support for this population.

New insights into anti-diabetes effects and molecular mechanisms of dietary saponins

Diabetes mellitus (DM) is a long-term metabolic disorder that manifests as chronic hyperglycemia and impaired insulin, bringing a heavy load on the global health care system. Considering the inevitable side effects of conventional anti-diabetic drugs, saponins-rich natural products exert promising therapeutic properties to serve as safer and more cost-effective alternatives for DM management. Herein, this review systematically summarized the research progress on the anti-diabetic properties of dietary saponins and their underlying molecular mechanisms in the past 20 years. Dietary saponins possessed the multidirectional anti-diabetic capabilities by concurrent regulation of various signaling pathways, such as IRS-1/PI3K/Akt, AMPK, Nrf2/ARE, NF-κB-NLRP3, SREBP-1c, and PPARγ, in liver, pancreas, gut, and skeletal muscle. However, the industrialization and commercialization of dietary saponin-based drugs are confronted with a significant challenge due to the low bioavailability and lack of the standardization. Hence, in-depth evaluations in pharmacological profile, function-structure interaction, drug-signal pathway interrelation are essential for developing dietary saponins-based anti-diabetic treatments in the future.

Pharmacological treatment of hypertension guided by peripheral or central blood pressure: a comparison between the two strategies

Background

Arterial hypertension treatment guided by central blood pressures (CPB) rather than peripheral blood pressures (PBP) measurement has the potential to show greater effectiveness in preventing or even regressing stiffness and target organ damage (TOD).

Objective

This study aimed to compare the parameters of CBP and PBP measurements, arterial stiffness, TOD and renal profile in patients with anti-hypertensive treatment guided by CBP or PBP targets.

Methods

A randomized clinical trial was conducted in central group (CG) and peripheral group (PG). Patients were randomized, evaluated every 3 months for BP and antihypertensive adjustments during a one-year follow up. The procedures in V1 and V5: anthropometric assessment; CBP/PBP measurements, carotid ultrasound; echocardiography; laboratory tests. Paired and unpaired t-tests and the χ2 were used (significance level: 5%).

Results

The study evaluated 59 participants (30CG/29PG). The augmentation index (AIx) was higher in the CG (27.3% vs. 20.3%, p = 0.041). Intergroup analysis has found central diastolic BP lower in the CG (78.9 vs. 84.3 mmHg, p = 0.024) and the Alx difference between groups ceased to exist after a one-year follow-up. Intragroup comparisons, after intervention, showed a lower frequency of changed PWV (p < 0.001) and LVMI (p = 0.018) in the CG. The PG showed a higher frequency of changed PWV (p < 0.001) and LVMI (p = 0.003).

Conclusion

The intervention guided by central BP reduced the central diastolic BP and AIx compared to the PG. There was a reduction in the frequency of changed PWV and LVMI in the CG.

Impact of Normal and Overweight Pregnancy in GLUT4 and Glucose-Dependent Vascular Contractility

INTRODUCTION

Obesity during pregnancy can contribute to hypertensive complications through changes in glucose utilization. We investigated the impact of vascular glucose uptake, GLUT4 density, and endothelium on agonist-induced vasoconstriction in the aortas of overweight pregnant rats.

METHODS

Isolated aortic rings with or without endothelium from pregnant or nonpregnant rats fed a standard (SD) or hypercaloric diet (HD) were contracted with phenylephrine or serotonin (10-9 to 10-4M) using standard (11 mm) or without (0 mm) glucose Krebs solution. GLUT4 density in the aortas was measured using the en face method.

RESULTS

Aortas from overweight pregnant animals (PHD) showed increased Phe-induced vasoconstriction (p < 0.05 vs. pregnant standard diet [PSD]), which was endothelium-independent. The contraction decreased significantly in the absence of glucose. In contrast, vessels from pregnant SD rats maintained their contraction in glucose-free Krebs solution. 5-HT increases PHD aortic contraction only in the absence of glucose. The fetal aortas from PHD mothers showed blunted vasoconstriction. Overweight significantly reduced GLUT4 expression in maternal and fetal aortas (p < 0.05 vs. PSD).

CONCLUSIONS

Aortic contractility is independent of glucose uptake during healthy pregnancy. In contrast, overweight pregnancy increases contractility. This increase depends directly on smooth muscle glucose uptake and inversely on GLUT-4 density. The increased contraction observed in the vasculature of overweight mothers was inverted in the fetal aortas.

Clusters of rare disorders and congenital anomalies in South America

Objective

To map geographic clusters of rare disorders and congenital anomalies reported in South America.

Methods

Qualitative systematic review conducted in Medline/PubMed, Lilacs, and Scielo electronic databases to identify studies meeting eligibility criteria. The strategy resulted in 1 672 unique articles, from which 164 were selected for full reading by a pair of reviewers.

Results

Fifty-five articles reported at least one cluster of genetic disorders or congenital anomalies in South American territory. From these papers, 122 clusters were identified, of which half (61) were related to autosomal recessive disorders. Sixty-five (53.3%) of the clusters were located in Brazil.

Conclusions

The results of the review reinforce that rare diseases and congenital anomalies can occur in a non-random way in space, which is discussed in the perspective of the complex history of formation, social organization, and genetic structure of the South American population. Mapping clusters in population medical genetics can be an important public health tool, given that such places concentrate cases of rare diseases that frequently require multiprofessional, specialized care. Therefore, these results can support important agendas in public health related to rare diseases and congenital anomalies, such as health promotion and surveillance.

Effect of Behavior Change Communication on Self-Care Practices Among Adult Type-2 Diabetic Patients in a Semi-urban Community of South India: A Quasi-Experimental Study

BACKGROUND

Diabetes mellitus is often termed the modern epidemic, and India ranks second after China in the global disease burden. Practice and adherence to essential self-care behaviors, positively correlated with good glycemic control and reduced complications in people with diabetes, have been inadequately understood, especially in a semi-urban setting.

METHODS

This community-based interventional study was done among 269 known adult type 2 diabetic patients from a semi-urban community in South India for three months. By simple random sampling, known diabetics identified in the health survey by the tertiary care teaching institute were considered for the study. Self-care practices in diabetes were recorded in the pre-test using a validated semi-structured questionnaire. Two health education sessions, each for 30 minutes, were conducted with 15-20 subjects in a group. Health education materials on self-care in diabetes, such as charts, handouts, video clippings, and PowerPoint presentations in the local language, were used. The self-care practices were re-recorded in the post-test after two months. Inferential statistics were carried out with a t-test, analysis of variance (ANOVA), and Pearson correlation coefficient, and a p-value less than 0.05 was considered statistically significant.  Results: A total of 253 diabetic subjects were included in the final analysis, with an attrition rate of 6%. The mean age of participants was 56.5 ± 11.9 years. The mean score of self-care practices among diabetic subjects at the baseline was 14.6 ± 13.2. Illiteracy and smoking habit were significantly associated with lower self-care scores in the pre-test. In the post-test, after health education, there was a significant improvement in the mean self-care practices score and a reduction in the mean fasting blood sugar level. Also, a significant mild negative correlation between the self-care scores and blood sugar levels was seen (Pearson correlation coefficient = -0.21, p < 0.001).

CONCLUSION

Self-care practices, which were not satisfactory in most diabetic participants, were found to be significantly impacted by the small group education. This stresses the need for effective health education sessions as envisaged under the national program.

Atherogenic index of plasma and its cardiovascular risk factor correlates among patients with type 2 diabetes in Uganda

Background

Atherogenic Index of Plasma (AIP) is a reliable predictor of coronary artery disease. There is paucity of data on AIP and its correlates among patients with type 2 diabetes (T2D) in Uganda.

Objective

To assess the profile of AIP and its cardiovascular risk factor correlates among patients with T2D in Uganda.

Methods

This was a cross-sectional study conducted in 8 health facilities with established T2D clinics in Central-Uganda. The study enrolled 500 patients aged 40 to 79 years. Data was collected on socio-demographic characteristics, lipid profile and glycated haemoglobin (HbA1c). The AIP was derived using log (triglycerides/high-density cholesterol) and further categorised as low cardiovascular disease (CVD) risk if the AIP was <0.1, intermediate risk (0.1-0.24) and high risk (≥0.24). Cardiovascular risk factors were defined according to international guidelines.Stata version 14 was used to analyse data, Pearson correlation analyses were conducted. Statistical significance was set at p<0.05.

Results

There were 389(77.4%) females with a mean age of 55.07±8. 979 years. Low-risk was found in 43.6%, intermediate risk in 20.2% and high risk in 36.2% of the participants. AIP significantly correlated with waist circumference (r=0.1095, p<0.0147), waist-hip ratio (r=0.1926, p<0.001), Casteri Risk Index I (r=0.506, r=<0.001), Casteri Risk Index II (r=0.246, p<0.001) and atherogenic coefficient (r=0.186, p<0.001). Insignificant correlation was observed between AIP and fasting blood sugar (r=0.017, p=0.7042), HBA1C (r=0.0108, p=0.8099) and diabetes duration (r=0.0445, p=0.32).

Conclusions

AIP is significantly elevated and correlated with cardiovascular risk factors in patients with T2D. In clinical management, this may be a useful tool in risk stratifying patients with T2D.

Implications of Transglutaminase-Mediated Protein Serotonylation in the Epigenetic Landscape, Small Cell Lung Cancer, and Beyond

In the case of small-cell lung carcinoma, the highly metastatic nature of the disease and the propensity for several chromatin modifiers to harbor mutations suggest that epigenetic manipulation may also be a promising route for oncotherapy, but histone deacetylase inhibitors on their own do not appear to be particularly effective, suggesting that there may be other regulatory parameters that dictate the effectiveness of vorinostat's reversal of histone deacetylation. Recent discoveries that serotonylation of histone H3 alters the permissibility of gene expression have led to renewed attention to this rare modification, as facilitated by transglutaminase 2, and at the same time introduce new questions about whether this modification belongs to a part of the concerted cohort of regulator events for modulating the epigenetic landscape. This review explores the mechanistic details behind protein serotonylation and its possible connections to the epigenome via histone modifications and glycan interactions and attempts to elucidate the role of transglutaminase 2, such that optimizations to existing histone deacetylase inhibitor designs or combination therapies may be devised for lung and other types of cancer.

Maternal stress induced endoplasmic reticulum stress and impaired pancreatic islets’ insulin secretion via glucocorticoid receptor upregulation in adult male rat offspring

Exposure to perinatal (prenatal and/or postnatal) stress is considered as a risk factor for metabolic disorders in later life. Accordingly, this study aimed to investigate the perinatal stress effects on the pancreatic endoplasmic reticulum (ER) stress induction, insulin secretion impairment and WFS1 (wolframin ER transmembrane Glycoprotein, which is involved in ER homeostasis and insulin secretion) expression changes, in rat offspring. According to the dams’ period of exposure to variable stress, their male offspring were divided into, control (CTRL); pre-pregnancy, pregnancy, lactation stress (PPPLS); pre-pregnancy stress (PPS); pregnancy stress (PS); lactation stress (LS); pre-pregnancy, pregnancy stress (PPPS); pregnancy, lactation stress (PLS); pre-pregnancy, lactation stress (PPLS) groups. Offspring pancreases were removed for ER extraction and the assessment of ER stress biomarkers, WFS1 gene DNA methylation, and isolated islets’ insulin secretion. Glucose tolerance was also tested. In the stressed groups, maternal stress significantly increased plasma corticosterone levels. In PPS, PS, and PPPS groups, maternal stress increased Bip (Hsp70; heat shock protein family A member 4), Chop (Ddit3; DNA- damage inducible transcript3), and WFS1 protein levels in pancreatic extracted ER. Moreover, the islets’ insulin secretion and content along with glucose tolerance were impaired in these groups. In PPS, PS, LS and PPPS groups, the pancreatic glucocorticoid receptor (GR) expression increased. Maternal stress did not affect pancreatic WFS1 DNA methylation. Thus, maternal stress, during prenatal period, impaired the islets’ insulin secretion and glucose homeostasis in adult male offspring, possibly through the induction of ER stress and GR expression in the pancreas, in this regard the role of WFS1 protein alteration in pancreatic ER should also be considered.

NT-ProBNP and mortality across the spectrum of glucose tolerance in the general US population

Background

Even though hyperglycemia is a well-known cardiovascular risk factor, the absolute risk of cardiovascular events varies to a great extent within each glycemic category. The aim of this study is to evaluate whether N-terminal pro-B natriuretic peptide (NT-ProBNP) could help identify subjects at higher cardiovascular risk, independently of blood glucose levels.

Methods

Serum NT-ProBNP levels were measured in 5502 people aged 45–79 years without heart failure from the general population (3380 with normoglycemia, 1125 with pre-diabetes and 997 with diabetes) that participated in the 1999–2004 cycles of the National Health and Nutrition Examination Survey. We applied Cox and Fine Gray models adjusted for cardiovascular risk factors to evaluate the association between NT-ProBNP levels and all-cause and cardiovascular mortality through December 2015.

Results

After a median follow-up of 13 years, 1509 participants died, 330 of cardiovascular causes. In the multivariable-adjusted models, compared with participants with NT-ProBNP < 100 pg/ml, those with levels 100–300 pg/ml and ≥ 300 pg/ml had a higher incidence of both all-cause mortality (HR 1.61, 95% CI 1.12–2.32, p = 0.012 and HR 2.96, 95% CI 1.75–5.00, p < 0.001, respectively) and cardiovascular mortality (HR 1.57, 95% CI 1.17–2.10, p = 0.011 and HR 2.08, 95% CI 1.47–2.93, p < 0.001, respectively). The association was consistent in subgroup analyses based on glycemic status, obesity, age and sex.

Conclusions

Elevated NT-ProBNP is independently associated with all-cause and cardiovascular mortality in the general population and could help identify patients at the highest risk. Further studies are needed to evaluate whether intensification of treatment based on biomarker data might lead to improvements in cardiovascular risk reduction.

Impaired functional exercise capacity and greater cardiovascular response to the 6-min walk test in congenital generalized lipodystrophy

BACKGROUND

Congenital Generalized Lipodystrophy (CGL) is an ultra-rare disease characterized by metabolic disorders. However, the evaluation of functional exercise capacity, cardiovascular (CV) response to exercise, and peripheral arterial disease (PAD) in CGL is scarce. Here we evaluated the performance and CV response to exercise and their association with PAD in CGL compared to healthy individuals.

METHODS

Twelve CGL and 12 healthy subjects matched for age and gender were included. Functional exercise capacity, CV response, and PAD were measured using the six-minute walk test (6MWT) and ankle-brachial index (ABI), respectively.

RESULTS

At baseline, CGL subjects showed reduced predicted walked distance (6MWD) (p = 0.009) and increased heart rate (HR), systolic (SBP), and diastolic (DBP) pressures compared to healthy subjects (p < 0.05). Most CGL subjects presented normal ABI values (1.0 ≤ ABI ≤ 1.4). Only 25% (n = 3) had ABI ≤ 0.9. CGL subjects did not present changes in ABI and blood pressure 12 months after metreleptin (MLP) replacement, but they walked a greater 6MWD than baseline (p = 0.04). Further, 6MWD and right ABI measurements were positively correlated in CGL subjects (p = 0.03). Right ABI negatively correlated with glucose, triglycerides, and VLDL-c (p < 0.05).

CONCLUSIONS

We observed that CGL subjects had lower functional exercise capacity and higher cardiovascular effort for similar performance of 6MWT, suggesting that strategies for decreasing exercise effort in this population should be essential. Furthermore, better physical performance was associated with high ABI in CGL. Additional studies are needed to clarify leptin's role in preserving functional exercise capacity in CGL.

ANTIBACTERIAL EFFECTS OF SINGLE AND COMBINED CRUDE EXTRACTS OF SYNADENIUM GLAUCESCENS AND COMMIPHORA SWYNNERTONII

Background

Synadenium glaucescens and Commiphora swynnertonii are among the reported plants used traditionally for treatment of bacterial infections. This study reports antibacterial effects of single and combined extracts from leaves, stem and root barks of Commiphora swynnertonii and Synadenium glaucescens.

Materials and Methods

Plants were collected from Manyara and Njombe regions in Tanzania. Extraction was done using dichloromethane and methanol. The extracts were assessed for antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa). Minimum Inhibitory Concentrations (MIC) was determined by broth microdilution, while Fractional Inhibitory Concentration (FIC) indices were calculated from MIC values of combined extracts to determine combination effects.

Results

Strong antibacterial activities were demonstrated by all extracts of S. glaucescens (MIC 0.011-0.375mg/mL) against Gram-positive bacteria and methanol extracts of C. swynnertonii (MIC 0.047-0.375mg/mL). Synergistic effect was observed when combining methanol extracts of C. swynnertonii stem bark with S. glaucescens leaves against S. aureus (∑FIC 0.5), Other synergistic effects were observed against E. faecalis with dichloromethane extracts of C. swynnertonii stem bark and S. glaucescens stem bark (∑FIC 0.5), and C. swynnertonii root bark and S. glaucescens root bark (FIC index 0.3). For the remaining combinations, mainly additive effects were observed.

Conclusion

Synergistic effects on bacteria were observed by combining different plant parts of S. glaucescens and C. swynnertonii suggesting that it could be beneficial to combine such extracts when used for antibacterial purposes.

Glucose enrichment impair neurotransmission and induce Aβ oligomerization that cannot be reversed by manipulating O-β-GlcNAcylation in the C. elegans model of Alzheimer's disease

Amyloid beta (Aβ) plaques formation and impaired neurotransmission and neuronal behaviors are primary hallmarks of Alzheimer's disease (AD) that are further associated with impaired glucose metabolism in elderly AD's patients. However, the exact role of glucose metabolism on disease progression has not been elucidated yet. In this study, the effect of glucose on Aβ-mediated toxicity, neurotransmission and neuronal behaviors has been investigated using a C. elegans model system expressing human Aβ. In addition to regular diet, worms expressing Aβ were supplemented with different concentrations of glucose and glycerol and 5 mM 2-deoxyglucose to draw any conclusions. Addition of glucose to the growth medium delayed Aβ-associated paralysis, promoted abnormal body shapes and movement, unable to restore impaired acetylcholine neurotransmission, inhibited egg laying and hatching in pre-existing Aβ-mediated pathology. The harmful effects of glucose may associate with an increase in toxic Aβ oligomers and impaired neurotransmission. O-β-GlcNAcylation (O-GlcNAc), a well-known post-translational modification is directly associated with glucose metabolism and has been found to ameliorates the Aβ- toxicity. We reasoned that glucose addition might induce O-GlcNAc, thereby protect against Aβ. Contrary to our expectations, induced glucose levels were not protective. Increasing O-GlcNAc, either with Thiamet-G (TMG) or by suppressing the O-GlcNAcase (oga-1) gene does interfere with and, therefore, reduce Aβ- toxicity but not in the presence of high glucose. The effects of glucose cannot be effectively managed by manipulating O-GlcNAc in AD models of C. elegans. Our observations suggest that glucose enrichment is unlikely to be an appropriate therapy to minimize AD progression.

Premature Coronary Artery Disease and Plasma Levels of Interleukins; a Systematic Scoping Review and Meta-Analysis

Introduction

Interleukins (ILs) can act as a predictive indicator of Premature Coronary Artery Disease (pCAD) and may be useful in screening of high-risk patients. However, there is no consensus on the relationship of serum levels of ILs and pCAD, yet. As a result, this study has been conducted in order to review the literature on the relationship between serum levels of different ILs and pCAD.

Methods

Medline, Scopus, Embase, and Web of Science databases were searched until December 7^th 2020. Two reviewers independently screened and summarized eligible articles. A meta-analysis was performed to assess the relationship of ILs and pCAD.

Results

12 case-control articles were included. IL-6 plasma changes do happen in pCAD patients with a standardized mean difference (SMD) of 0.51 (95% CI: 0.12-0.90; p=0.010) compared with the control group. This difference was also observed when evaluating the plasma levels of IL-1 and IL-17, with an SMD of 1.42 (95% CI: 1.11-1.73; p<0.001) and 0.59 (95% CI: 0.14-1.04; p=0.011), respectively. Meanwhile, no significant difference existed in plasma levels of IL-10 (SMD=0.26; 95% CI: -0.17-0.70; p=0.236), and IL-18 (SMD=1.44; 95% CI: -0.19-3.07; p=0.083) between pCAD patients and those in the control group.

Conclusion

Low level of evidence showed that there may be a significant relationship between increased plasma levels of ILs and the occurrence of pCAD. As a result, prospective cohort studies with serial assessments of serum ILs during follow up period, focusing on controlling classical risk factors of pCAD and increase in level of ILs, should be conducted.

Dietary regulations for microbiota dysbiosis among post-menopausal women with type 2 diabetes

Type 2 diabetes (T2D) and T2D-associated comorbidities, such as obesity, are serious universally prevalent health issues among post-menopausal women. Menopause is an unavoidable condition characterized by the depletion of estrogen, a gonadotropic hormone responsible for secondary sexual characteristics in women. In addition to sexual dimorphism, estrogen also participates in glucose-lipid homeostasis, and estrogen depletion is associated with insulin resistance in the female body. Estrogen level in the gut also regulates the microbiota composition, and even conjugated estrogen is actively metabolized by the estrobolome to maintain insulin levels. Moreover, post-menopausal gut microbiota is different from the pre-menopausal gut microbiota, as it is less diverse and lacks the mucolytic Akkermansia and short-chain fatty acid (SCFA) producers such as Faecalibacterium and Roseburia. Through various metabolites (SCFAs, secondary bile acid, and serotonin), the gut microbiota plays a significant role in regulating glucose homeostasis, oxidative stress, and T2D-associated pro-inflammatory cytokines (IL-1, IL-6). While gut dysbiosis is common among post-menopausal women, dietary interventions such as probiotics, prebiotics, and synbiotics can ease post-menopausal gut dysbiosis. The objective of this review is to understand the relationship between post-menopausal gut dysbiosis and T2D-associated factors. Additionally, the study also provided dietary recommendations to avoid T2D progression among post-menopausal women.

Type 2 diabetes mellitus patients' lived experience at a tertiary hospital in Ekiti State, Nigeria

Diabetes mellitus is a complex and chronic metabolic disorder that is associated with multiple complications and disabilities. This contributes to increased mortality and poor quality of life among affected individuals. The study explored the lived experience of patients with type 2 diabetes mellitus at a Teaching Hospital in Ekiti State, Nigeria. A mixed method of qualitative and quantitative design was adopted. For the quantitative aspect, a convenience sampling technique was employed while the instrument used was an adapted questionnaire. For the qualitative aspect, focus-group discussion involving twenty-four participants was conducted, and the sample size was determined by data saturation. Qualitative data was analyzed using thematic transcription. Findings revealed that 55.6% of the participants were females while 63.5% had tertiary education. Majority (18 of 24) of the respondents experienced body weakness, frequent urination and excessive thirst when diagnosed of diabetes mellitus and later experienced occasional body weakness, burning sensation, tingling and numbness of the feet, fatigue, loss of libido, and occasional visual disturbance. Two-third of the participants reported being indifferent when they were informed about their condition. However, majority of the participants perceived that the cause of diabetes mellitus was heredity. More than two-third of the participants did not experience reduction in their normal daily activities but rather experienced occasional emotional disturbances, anxiety and challenges with self-management of diabetes and this was associated with maintaining a normo-glycemic state due to the financial implications of drugs and dietary modifications.

NT-proBNP as a predictor of death and cardiovascular events in patients with type 2 diabetes

Existing risk prediction scores based on clinical and laboratory variables have been considered inaccurate in patients with Type 2 Diabetes Mellitus (T2DM). Circulating concentrations of natriuretic peptides have been used to aid in the diagnosis and to predict outcomes in heart failure. However, there is a growing body of evidence for the use of natriuretic peptides measurements, mainly N-terminal pro-B-type natriuretic peptide (NT-proBNP), as a tool in risk stratification for individuals with T2DM. Studies have demonstrated the ability of NT-proBNP to improve outcomes prediction when incorporated into multivariate models. More recently, evidence has emerged of the discriminatory power of NT-proBNP, demonstrating, as a single variable, a similar and even superior ability to multivariate risk models for the prediction of death and cardiovascular events in individuals with T2DM. Natriuretic peptides are synthesized and released from the myocardium as a counter-regulatory response to increased cardiac wall stress, sympathetic tone, and vasoconstriction, acting on various systems and affecting different biological processes. In this article, we present a review of the accumulated knowledge about these biomarkers, underscoring the strength of the evidence of their predictive ability for fatal and non-fatal outcomes. It is likely that, by influencing the functioning of many organs, these biomarkers integrate information from different systems. Although not yet recommended by guidelines, measurement of natriuretic peptides, and particularly NT-proBNP, should be strongly considered in the risk stratification of individuals with T2DM.

Dynamic transcriptome analysis of the muscles in high-fat diet-induced obese zebrafish (Danio rerio) under 5-HT treatment

Peripheral 5-hydroxytryptamine (5-HT, also called serotonin) is reportedly a potential therapeutic target in obesity-related metabolic diseases due to its regulatory role in energy homeostasis in mammals. However, information on the detailed effect of peripheral 5-HT on the energy metabolism in fishes, especially the lipid metabolism, and the underlying mechanism remains elusive. In this study, a diet-induced obesity model was developed in the zebrafish (Danio rerio), a prototypical animal model for metabolic disorders. The zebrafish were fed a high-fat diet for 8 weeks and were simultaneously injected with PBS, 0.1 mM and 10 mM 5-HT, intraperitoneally. The body weight was significantly lower in the zebrafish injected with 0.1 mM 5-HT (P < 0.05), however, there was no change in body length (P > 0.05) at the end of the 8-week treatment. The muscle tissues from the zebrafish treated with PBS and 5-HT were collected for transcriptomic analysis and the RNA-seq revealed 1134, 3713, and 2535 genes were screened out compared to the muscular DEGs among three groups. The enrichment analysis revealed DEGs to be significantly associated with multiple metabolic pathways, including ribosome, oxidative phosphorylation, proteasome, PPAR signaling pathway, and ferroptosis. Additionally, the qRT-PCR validated 12 DEGs out of which 10 genes exhibited consistent trends. Taken together, this data provided useful information on the transcriptional characteristics of the muscle tissue in the obese zebrafish exposed to 5-HT, offering important insights into the regulatory effect of peripheral 5-HT in teleosts, as well as novel approaches for preventing and treating obesity-related metabolic dysfunction.

Beneficial cardiovascular and remodeling effects of SGLT2 inhibitors: pathophysiologic mechanisms

INTRODUCTION

The intent of this paper is to review the data regarding the multipotential effects of the sodium-glucose cotransporter 2 (SGLT 2) inhibitors, their cardiovascular protective effects, and their mechanism of action.

AREAS COVERED

The SGLT2 inhibitors exert their beneficial antidiabetic and cardioprotective effects through increased glucose excretion from the kidneys, blood pressure and weight lowering, vasodilation and other potential beneficial effects. They have been used for the treatment of patients with type 2 diabetes mellitus (T2DM) as well as in patients with cardiovascular disease (CVD), coronary artery disease (CAD),and heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). In order to get a better understanding of their mechanism of action for their multiple cardiovascular protective effects, a Medline search of the English language literature was conducted between 2015 and February 2022 and 46 pertinent papers were selected.

EXPERT OPINION

The analysis of data clearly demonstrated that the use of the SGLT2 inhibitors besides their antidiabetic effects, provide additional protection against CVD, CAD, and HFrEF and HFpEF, and death, but not stroke, in both diabetic and non-diabetic patients. Therefore, they should be preferably used for the treatment of patients with T2DM with preexisting CVD, CAD, and HFrEF and HFpEF.

Night shift work characteristics are associated with several elevated metabolic risk factors and immune cell counts in a cross-sectional study

Night shift work is associated with increased health risks. Here we examined the association of metabolic risk factors and immune cell counts, with both night shift work and particular characteristics thereof: frequency, duration and consecutive night shifts. We performed a cross-sectional study using data from 10,201 non-shift workers and 1062 night shift workers of the Lifelines Cohort study. Linear regression analyses, adjusted for demographic, lifestyle and occupational factors, were used to study associations of night shift work characteristics with metabolic risk factors and immune cell counts. Night shift workers had an increased BMI, waist circumference and immune cell counts compared to non-shift workers. This was especially seen in night shift workers who had a higher frequency of night shifts per month (≥ 5: BMI: B = 0.81 kg/m² (95%-CI = 0.43–1.10); waist circumference: B = 1.58 cm (95%-Cl = 0.34–1.71; leukocytes: B = 0.19 × 10⁹ cells/L (95%-CI = 0.04–0.34 × 10⁹)) and worked more consecutive night shifts (> 3: BMI: B = 0.92 kg/m² (95%-CI = 0.41–1.43); waist circumference: B = 1.85 cm (95%-Cl = 0.45–3.24); leukocytes: B = 0.32 × 10⁹ cells/L (95%-CI = 0.09–0.55 × 10⁹)). This association was less pronounced in long-term night shift workers (≥ 20 years). Our findings provide evidence for the association between night shift work characteristics and BMI, waist circumference and leukocytes (including, monocytes, lymphocytes, and basophil granulocytes).

Serotonin: an overlooked regulator of endocytosis and endosomal sorting?

Serotonin is a neurotransmitter and a hormone that is typically associated with regulating our mood. However, the serotonin transporter and receptors are expressed throughout the body, highlighting the much broader, systemic role of serotonin in regulating human physiology. A substantial body of data strongly implicates serotonin as a fundamental regulator of endocytosis and endocytic sorting. Serotonin has the potential to enhance endocytosis through three distinct mechanisms - serotonin signalling, serotonylation and insertion into the plasma membrane - although the interplay and relationship between these mechanisms has not yet been explored. Endocytosis is central to the cellular response to the extracellular environment, controlling receptor distribution on the plasma membrane to modulate signalling, neurotransmitter release and uptake, circulating protein and lipid cargo uptake, and amino acid internalisation for cell proliferation. Uncovering the range of cellular and physiological circumstances in which serotonin regulates endocytosis is of great interest for our understanding of how serotonin regulates mood, and also the fundamental understanding of endocytosis and its regulation throughout the body. This article has an associated Future Leader to Watch interview with the first author of the paper.

Single or combined ablation of peripheral serotonin and p21 limit adipose tissue expansion and metabolic alterations in early adulthood in mice fed a normocaloric diet

Identifying the fundamental molecular factors that drive weight gain even in the absence of hypercaloric food intake, is crucial to enable development of novel treatments for the global pandemic of obesity. Here we investigated both adipose tissue-specific and systemic events that underlie the physiological weight gain occurring during early adulthood in mice fed a normocaloric diet. In addition, we used three different genetic models to identify molecular factors that promote physiological weight gain during normocaloric and hypercaloric diets. We demonstrated that normal physiological weight gain was accompanied by an increase in adipose tissue mass and the presence of cellular and metabolic signatures typically found during obesity, including adipocyte hypertrophy, macrophage recruitment into visceral fat and perturbed glucose metabolism. At the molecular level, this was associated with an increase in adipose tissue tryptophan hydroxylase 1 (Tph1) transcripts, the key enzyme responsible for the synthesis of peripheral serotonin. Genetic inactivation of Tph1 was sufficient to limit adipose tissue expansion and associated metabolic alterations. Mechanistically, we discovered that Tph1 inactivation resulted in down-regulation of cyclin-dependent kinase inhibitor p21Waf1/Cip1 expression. Single or double ablation of Tph1 and p21 were equally effective in preventing adipocyte expansion and systemic perturbation of glucose metabolism, upon both normocaloric and hypercaloric diets. Our results suggest that serotonin and p21 act as a central molecular determinant of weight gain and associated metabolic alterations, and highlights the potential of targeting these molecules as a pharmacologic approach to prevent the development of obesity.

The physiology, pathology and potential therapeutic application of serotonylation

The classical neurotransmitter serotonin or 5-hydroxytryptamine (5-HT), synthesized from tryptophan, can be produced both centrally and peripherally. Through binding to functionally distinct receptors, serotonin is profoundly implicated in a number of fundamental physiological processes and pathogenic conditions. Recently, serotonin has been found covalently incorporated into proteins, a newly identified post-translational modification termed serotonylation. Transglutaminases (TGMs), especially TGM2, are responsible for catalyzing the transamidation reaction by transferring serotonin to the glutamine residues of target proteins. Small GTPases, extracellular matrix protein fibronectin, cytoskeletal proteins and histones are the most reported substrates for serotonylation, and their functions are triggered by this post-translational modification. This Review highlights the roles of serotonylation in physiology and diseases and provides perspectives for pharmacological interventions to ameliorate serotonylation for disease treatment.

Performance of the recommended ESC/EASD cardiovascular risk stratification model in comparison to SCORE and NT-proBNP as a single biomarker for risk prediction in type 2 diabetes mellitus

BACKGROUND

Recently, the European Society of Cardiology (ESC) and European Association for the Society of Diabetes (EASD) introduced a new cardiovascular disease (CVD) risk stratification model to aid further treatment decisions in individuals with diabetes. Our study aimed to investigate the prognostic performance of the ESC/EASD risk model in comparison to the Systematic COronary Risk Evaluation (SCORE) risk model and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in an unselected cohort of type 2 diabetes mellitus (T2DM).

METHODS AND RESULTS

A total of 1690 T2DM patients with a 10-year follow up for fatal CVD and all-cause death and a 5-year follow up for CVD and all-cause hospitalizations were analyzed. According to ESC/EASD risk criteria 25 (1.5%) patients were classified as moderate, 252 (14.9%) high, 1125 (66.6%) very high risk and 288 (17.0%) were not classifiable. Both NT-proBNP and SCORE risk model were associated with 10-year CVD and all-cause death and 5-year CVD and all-cause hospitalizations while the ESC/EASD model was only associated with 10-year all-cause death and 5-year all-cause hospitalizations. NT-proBNP and SCORE showed significantly higher C-indices than the ESC/EASD risk model for CVD death [0.80 vs. 0.53, p < 0.001; 0.64 vs. 0.53, p = 0.001] and all-cause death [0.73, 0.66 vs. 0.52, p < 0.001 for both]. The performance of SCORE improved in a subgroup without CVD aged 40-64 years compared to the unselected cohort, while NT-proBNP performance was robust across all groups.

CONCLUSION

The new introduced ESC/EASD risk stratification model performed limited compared to SCORE and single NT-proBNP assessment for predicting 10-year CVD and all-cause fatal events in individuals with T2DM.

Distinctive Metabolomics Patterns Associated With Insulin Resistance and Type 2 Diabetes Mellitus

Obesity is associated with an increased risk of insulin resistance (IR) and type 2 diabetes mellitus (T2DM) which is a multi-factorial disease associated with a dysregulated metabolism and can be prevented in pre-diabetic individuals with impaired glucose tolerance. A metabolomic approach emphasizing metabolic pathways is critical to our understanding of this heterogeneous disease. This study aimed to characterize the serum metabolomic fingerprint and multi-metabolite signatures associated with IR and T2DM. Here, we have used untargeted high-performance chemical isotope labeling (CIL) liquid chromatography-mass spectrometry (LC-MS) to identify candidate biomarkers of IR and T2DM in sera from 30 adults of normal weight, 26 obese adults, and 16 adults newly diagnosed with T2DM. Among the 3633 peak pairs detected, 62% were either identified or matched. A group of 78 metabolites were up-regulated and 111 metabolites were down-regulated comparing obese to lean group while 459 metabolites were up-regulated and 166 metabolites were down-regulated comparing T2DM to obese groups. Several metabolites were identified as IR potential biomarkers, including amino acids (Asn, Gln, and His), methionine (Met) sulfoxide, 2-methyl-3-hydroxy-5-formylpyridine-4-carboxylate, serotonin, L-2-amino-3-oxobutanoic acid, and 4,6-dihydroxyquinoline. T2DM was associated with dysregulation of 42 metabolites, including amino acids, amino acids metabolites, and dipeptides. In conclusion, these pilot data have identified IR and T2DM metabolomics panels as potential novel biomarkers of IR and identified metabolites associated with T2DM, with possible diagnostic and therapeutic applications. Further studies to confirm these associations in prospective cohorts are warranted.

Serotonin stimulated parathyroid hormone related protein induction in the mammary epithelia by transglutaminase-dependent serotonylation

Mammary-derived serotonin has been implicated in breast-to-bone communication during lactation by increasing parathyroid hormone related-protein (PTHrP) in the mammary gland. It is well established that PTHrP acts on the bone to liberate calcium for milk synthesis during lactation; however, the mechanism of serotonin’s regulation of PTHrP has not been fully elucidated. Recently, serotonylation has been shown to be involved in a variety of physiological processes mediated by serotonin. Therefore, we investigated whether serotonylation is involved in serotonin’s regulation of PTHrP in the mammary gland using lactogenically differentiated mouse mammary epithelial cells. We investigated the effect of increased intracellular serotonin using the antidepressant fluoxetine or 5-hydroxytryptophan (serotonin precursor), with or without transglutaminase inhibition and the corresponding action on PTHrP induction and activity. Treatment with fluoxetine or 5-hydroxytryptophan significantly increased intracellular serotonin concentrations and subsequently increased PTHrP gene expression, which was reduced with transglutaminase inhibition. Furthermore, we determined that transglutaminase activity is increased with lactogenic differentiation and 5-hydroxytryptophan or fluoxetine treatment. We investigated whether RhoA, Rac1, and Rab4 were potential serotonylation target proteins. We speculate that RhoA is potentially a serotonylation target protein. Our data suggest that serotonin regulates PTHrP induction in part through the process of serotonylation under lactogenic conditions in mouse mammary epithelial cells.

Application of magnetic nanoparticles in nucleic acid detection

Nucleic acid is the main material for storing, copying, and transmitting genetic information. Gene sequencing is of great significance in DNA damage research, gene therapy, mutation analysis, bacterial infection, drug development, and clinical diagnosis. Gene detection has a wide range of applications, such as environmental, biomedical, pharmaceutical, agriculture and forensic medicine to name a few. Compared with Sanger sequencing, high-throughput sequencing technology has the advantages of larger output, high resolution, and low cost which greatly promotes the application of sequencing technology in life science research. Magnetic nanoparticles, as an important part of nanomaterials, have been widely used in various applications because of their good dispersion, high surface area, low cost, easy separation in buffer systems and signal detection. Based on the above, the application of magnetic nanoparticles in nucleic acid detection was reviewed.

Dapagliflozin and cardiovascular outcomes in patients with Type 2 diabetes

The relationship between cardiovascular disease, heart failure (HF) and Type-2 diabetes (T2DM) is widely recognized. Cardiovascular (CV) outcome trials are required for all new glucose-lowering agents to confirm safety with respect to CV risk. CV outcome trials with SGLT2i inhibitors have shown CV benefit, with reductions in major CV events and HF. This review focuses on the DECLARE-TIMI 58 trial with dapagliflozin in T2DM, which showed noninferiority for major adverse cardiovascular events and reduction in hospitalization for HF and associated CV mortality in a broad range of patients with T2DM. The DAPA-HF trial of dapagliflozin in people with HF with reduced ejection fraction with and without T2DM confirms benefits for those with HF.

Transcriptomic analysis investigating the interaction between peripheral serotonin and high-fat diet feeding on mammary gene expression in midlactation mice

To understand the role of peripheral serotonin and its interaction with diet in midlactation mammary gene expression, our study uses tryptophan hydroxylase 1 knockout (Tph1-KO) mice fed a high-fat diet (HFD). It has previously been demonstrated that HFD feeding increases inflammatory and immune pathways in peak lactation mammary glands of mice and increases pup mortality in wild-type (WT) mice compared with dams fed a low-fat diet (LFD). Peripheral serotonin inhibition has been associated with resistance to obesity in male mice fed an HFD. Little is known about the function of Tph1 and how peripheral serotonin affects mammary gland function during pregnancy and lactation. In this study, WT and Tph1-KO models were used to investigate global transcriptomic changes in peak lactation mammary glands when dams were fed either an HFD or LFD. WT and Tph1-KO female mice were assigned to either an LFD or HFD beginning at 3 wk of age (n = 4/group). Dams were euthanized on lactation day 11. Differentially expressed genes (DEGs) were first filtered by adjusted P value (cutoff ≤ 0.05) and fold-change (FC, cutoff ≥2). Genes were further filtered by mean normalized read count with a cutoff ³10. We did not observe many differentially expressed genes in WT and Tph1-KO dams fed LFD. However, 3,529 DEGs were observed between WT-HFD and Tph1-KO-HFD mice, including cell cycle regulation and MAPK pathways being significantly enriched. Further research is required to completely understand the physiological significance of our results on peak lactation mammary physiology and the contribution of serotonin.

Serotonylation: Serotonin Signaling and Epigenetics

Serotonylation, the covalent linkage of serotonin to proteins has been discovered more than 60 years ago but only recently the mechanisms and first functions have been elucidated. It has been found that transglutaminases (TG) such as TG2 and the blood coagulation factor XIIIa are the enzymes which catalyze the linkage of serotonin and other monoamines to distinct glutamine (Gln) residues of target proteins. The first target proteins, small G-proteins and extracellular matrix constituents, were found in platelets and are pivotally involved in platelet aggregation and the formation of thrombi. The serotonylation of the same proteins is also involved in insulin secretion and in the proliferation of pulmonary vascular smooth muscle cells and thereby in the pathogenesis of pulmonary arterial hypertension (PAH). Recently histones have been described as targets of serotonylation opening the area of transcriptional control to this posttranslational protein modification. Future studies will certainly reveal further target proteins, signaling pathways, cellular processes, and diseases, in which serotonylation or, more general, monoaminylation is important.

Cardiovascular Effects of Liraglutide

BACKGROUND

Liraglutide is a glucagon-like 1 (GLP-1) agonist approved for treatment of type 2 diabetes and obesity.

OBJECTIVE

To review the cardiovascular effects of liraglutide including macrovascular and microvascular events, its use in heart failure, and its effects on heart rate and blood pressure.

RESULTS

The impact of liraglutide on cardiovascular outcomes was examined in a large welldesigned study published in 2016, the LEADER trial. This study included 9,340 patients with advanced type 2 diabetes and high baseline cardiovascular risk. The primary outcome was the first occurrence of death from cardiovascular causes, non-fatal myocardial infarction, or non-fatal stroke. After a median follow-up of 3.8 years, patients randomized to liraglutide had significant reduction in the composite primary outcome compared to patients randomized to placebo, hazard ratio (HR) 0.87; 95% CI 0.78-0.97. Death from cardiovascular causes was significantly reduced with liraglutide therapy (HR, 0.78; 95% CI 0.66-0.93), as well as death from any cause (HR, 0.85; 95% CI 0.74-0.97). In 2017, the LEADER investigators reported that nephropathy events were significantly lower after liraglutide therapy than placebo (HR 0.78; 95% CI 0.67-0.92), but there was no significant difference in retinopathy events. Meanwhile, other studies suggested that the use of liraglutide may be harmful in patients with severe heart failure, in part due to increase in heart rate.

CONCLUSION

Liraglutide is a useful therapy in patients with advanced type 2 diabetes complicated by cardiovascular disease, except patients with severe heart failure. Further studies are needed to evaluate the long-term effects of liraglutide, and to see whether its beneficial effects extend to patients with type 2 diabetes and low cardiac risk.

Quercetin and its metabolite isorhamnetin promote glucose uptake through different signalling pathways in myotubes

Quercetin and its metabolite isorhamnetin elicit various beneficial effects on human health. However, their bioavailability is low. In this study, we investigated whether low concentrations in the physiological range could promote glucose uptake in L6 myotubes, as well as the underlying molecular mechanisms. We found that 0.1 nM and 1 nM quercetin or 1 nM isorhamnetin significantly increased glucose uptake via translocation of glucose transporter type 4 (GLUT4) to the plasma membrane of L6 myotubes. Quercetin principally activated the CaMKKβ/AMPK signalling pathway at these concentrations, but also activated IRS1/PI3K/Akt signalling at 10 nM. In contrast, 1 nM and 10 nM isorhamnetin principally activated the JAK/STAT pathway. Treatment with siAMPKα and siJAK2 abolished quercetin- and isorhamnetin-induced GLUT4 translocation, respectively. However, treatment with siJAK3 did not affect isorhamnetin-induced GLUT4 translocation, indicating that isorhamnetin induced GLUT4 translocation mainly through JAK2, but not JAK3, signalling. Thus, quercetin preferably activated the AMPK pathway and, accordingly, stimulated IRS1/PI3K/Akt signalling, while isorhamnetin activated the JAK2/STAT pathway. Furthermore, after oral administration of quercetin glycoside at 10 and 100 mg/kg body weight significantly induced GLUT4 translocation to the plasma membrane of skeletal muscles in mice. In the same animals, plasma concentrations of quercetin aglycone form were 4.95 and 6.80 nM, respectively. In conclusion, at low-concentration ranges, quercetin and isorhamnetin promote glucose uptake by increasing GLUT4 translocation via different signalling pathways in skeletal muscle cells; thus, these compounds may possess beneficial functions for maintaining glucose homeostasis by preventing hyperglycaemia at physiological concentrations.

Transglutaminase in Receptor and Neurotransmitter-Regulated Functions

Transglutaminases (TGs) and especially TG2 play important roles in neurotransmitter and receptor signaling pathways. Three different mechanisms by which TG2 interacts with neurotransmitter and receptor signaling systems will be discussed in this review. The first way in which TG2 interacts with receptor signaling is via its function as a guanine nucleotide binding protein (G-protein) coupling to G-protein coupled receptors (GPCRs) to activate down-stream signaling pathways. TG2 can exist in a least two conformations, a closed GTP-bound conformation and an open calcium-bound conformation. In the closed GTP-bound conformation, TG2 is capable of functioning as a G-protein for GPCRs. In the open calcium-bound conformation, TG2 catalyzes a transamidation reaction cross-linking proteins or catalyzing the covalent binding of a mono- or polyamine to a protein. The second mechanism is regulation of the transamidation reaction catalyzed by TG2 via receptor stimulation which can increase local calcium concentrations and thereby increase transamidation reactions. The third way in which TG2 plays a role in neurotransmitter and receptor signaling systems is via its use of monoamine neurotransmitters as a substrate. Monoamine neurotransmitters including serotonin can be substrates for transamidation to a protein often a small G-protein (also known as a small GTPase) resulting in activation of the small G-protein. The transamidation of a monoamine neurotransmitter or serotonin has been designated as monoaminylation or more specifically serotonylation, respectively. Other proteins are also targets for monoaminylation such as fibronectin and cytoskeletal proteins. These receptor and neurotransmitter-regulated reactions by TG2 play roles in physiological and key pathophysiological processes.

Could use of Selective Serotonin Reuptake Inhibitors During Lactation Cause Persistent Effects on Maternal Bone?

The lactating mammary gland elegantly coordinates maternal homeostasis to provide calcium for milk. During lactation, the monoamine serotonin regulates the synthesis and release of various mammary gland-derived factors, such as parathyroid hormone-related protein (PTHrP), to stimulate bone resorption. Recent evidence suggests that bone mineral lost during prolonged lactation is not fully recovered following weaning, possibly putting women at increased risk of fracture or osteoporosis. Selective Serotonin Reuptake Inhibitor (SSRI) antidepressants have also been associated with reduced bone mineral density and increased fracture risk. Therefore, SSRI exposure while breastfeeding may exacerbate lactational bone loss, compromising long-term bone health. Through an examination of serotonin and calcium homeostasis during lactation, lactational bone turnover and post-weaning recovery of bone mineral, and the effect of peripartum depression and SSRI on the mammary gland and bone, this review will discuss the hypothesis that peripartum SSRI exposure causes persistent reductions in bone mineral density through mammary-derived PTHrP signaling with bone.

Sarcopenia: a chronic complication of type 2 diabetes mellitus

BACKGROUND

Diabetics are at increased risk for impaired mobility and strength, frequently related to the disease control. Sarcopenia is the reduction of muscle mass associated with the decrease in muscle strength and/or performance, resulting in worse morbidity in chronic diseases.

METHODS

The objectives of this paper was to assess the prevalence of sarcopenia in patients with type 2 diabetes mellitus (T2DM) and determine its association with diabetes characteristics, progression, and complications, as well as changes in bone mineral density. The sample consisted of patients with T2DM followed at the outpatient clinics of the Serviço de Endocrinologia e Metabologia do Hospital de Clínicas da Universidade Federal do Paraná, from March to August 2016. Participants were men and women above 18 years with T2DM diagnosed at least 1 year earlier. Individuals with chronic diseases, users of any drug that modifies body composition, patients with body mass index (BMI) > 35 or < 18 kg/m², and users of illicit drugs or hormonal or nutritional supplementation were excluded. The selected patients answered questionnaires about demographics, eating habits, and disease characteristics, and performed a bone densitometry exam in a dual energy absorptiometry (total body; spine and femur (total and neck)), a handgrip test by manual dynamometer, and an evaluation of the abdominal circumference (AC). The medical records were reviewed seeking diabetes data and laboratory test results. Patients were matched for sex, age, and race with healthy controls [Control Group (CG)]. The diagnosis of sarcopenia was conducted according to the criteria of the Foundation for National Institute of Health.

RESULTS

The final sample consisted of 83 patients in the DG and 83 in the CG. The DG had higher BMI, WC, past history of fractures and lower calcium and healthy diet intake (p < 0.005), compared to the CG. The DG presented a higher frequency of abnormal BMD (osteopenia in 45 (53%), and osteoporosis in 14 (19%)) and comorbidities than the CG (p < 0.005). Pre-sarcopenia was not different between groups, but muscle weakness was present in 25 diabetics (18 women) and only in 5 controls (4 men) (p = 0.00036). Sarcopenia was diagnosed in 13 (16.2%) patients in the DG and 2 (2.4%) in the CG (p = 0.01168). Pre-sarcopenia and sarcopenia were associated with altered BMD (p < 0.005), with no association with diabetes duration or control. Body mass index and osteoporosis increased the likelihood to have sarcopenia, but hypertension and healthy diet decreased it.

CONCLUSION

The DG had altered BMD associated with worse glycemic control, and a higher prevalence of sarcopenia, suggesting the need to look for their presence in diabetics.

Metabolic Syndrome and Antipsychotics: The Role of Mitochondrial Fission/Fusion Imbalance

Second-generation antipsychotics (SGAs) are known to increase cardiovascular risk through several physiological mechanisms, including insulin resistance, hepatic steatosis, hyperphagia, and accelerated weight gain. There are limited prophylactic interventions to prevent these side effects of SGAs, in part because the molecular mechanisms underlying SGAs toxicity are not yet completely elucidated. In this perspective article, we introduce an innovative approach to study the metabolic side effects of antipsychotics through the alterations of the mitochondrial dynamics, which leads to an imbalance in mitochondrial fusion/fission ratio and to an inefficient mitochondrial phenotype of muscle cells. We believe that this approach may offer a valuable path to explain SGAs-induced alterations in metabolic homeostasis.

Brazilian guidelines on prevention of cardiovascular disease in patients with diabetes: a position statement from the Brazilian Diabetes Society (SBD), the Brazilian Cardiology Society (SBC) and the Brazilian Endocrinology and Metabolism Society (SBEM)

BACKGROUND

Since the first position statement on diabetes and cardiovascular prevention published in 2014 by the Brazilian Diabetes Society, the current view on primary and secondary prevention in diabetes has evolved as a result of new approaches on cardiovascular risk stratification, new cholesterol lowering drugs, and new anti-hyperglycemic drugs. Importantly, a pattern of risk heterogeneity has emerged, showing that not all diabetic patients are at high or very high risk. In fact, most younger patients who have no overt cardiovascular risk factors may be more adequately classified as being at intermediate or even low cardiovascular risk. Thus, there is a need for cardiovascular risk stratification in patients with diabetes. The present panel reviews the best current evidence and proposes a practical risk-based approach on treatment for patients with diabetes.

MAIN BODY

The Brazilian Diabetes Society, the Brazilian Society of Cardiology, and the Brazilian Endocrinology and Metabolism Society gathered to form an expert panel including 28 cardiologists and endocrinologists to review the best available evidence and to draft up-to-date an evidence-based guideline with practical recommendations for risk stratification and prevention of cardiovascular disease in diabetes. The guideline includes 59 recommendations covering: (1) the impact of new anti-hyperglycemic drugs and new lipid lowering drugs on cardiovascular risk; (2) a guide to statin use, including new definitions of LDL-cholesterol and in non-HDL-cholesterol targets; (3) evaluation of silent myocardial ischemia and subclinical atherosclerosis in patients with diabetes; (4) hypertension treatment; and (5) the use of antiplatelet therapy.

CONCLUSIONS

Diabetes is a heterogeneous disease. Although cardiovascular risk is increased in most patients, those without risk factors or evidence of sub-clinical atherosclerosis are at a lower risk. Optimal management must rely on an approach that will cover both cardiovascular disease prevention in individuals in the highest risk as well as protection from overtreatment in those at lower risk. Thus, cardiovascular prevention strategies should be individualized according to cardiovascular risk while intensification of treatment should focus on those at higher risk.