Metabolic and Energy Imbalance in Dysglycemia-Based Chronic Disease

Insights into the molecular mechanisms of malnutrition-associated steatohepatitis: A review

Malnutrition is a public health epidemic mainly targeting poverty-stricken people, young ones, older people, pregnant women, and individuals with metabolic disorders. Severe malnutrition is linked with several metabolic defects, such as hepatic dysfunction, hypertension, cardiovascular disease, and osteoarthritis. The proper functioning of the liver plays a crucial role in ensuring the supply of nutrients to the body. Consequently, inadequate nutrition can lead to severe periportal hepatic steatosis due to compromised mitochondrial and peroxisome functions. Reduced protein intake disrupts essential metabolic processes like the TCA cycle, oxidative phosphorylation, and β-oxidation, ultimately affecting ATP production. Furthermore, this can trigger a cascade of events, including disturbances in amino acid metabolism, iron metabolism, and gut microbiota, which activate genes involved in de novo lipogenesis, leading to the accumulation of lipids in the liver. The condition, in prolonged cases, progresses to steatohepatitis and liver fibrosis. Limited therapeutic solutions are available; however, few dietary supplements and drugs have demonstrated positive effects on the growth and health of malnourished individuals. These supplements improve parameters such as inflammatory and oxidative status, reduce triglyceride accumulation, enhance insulin sensitivity, and downregulate gene expression in hepatic lipid metabolism. This review elucidates the various mechanisms involved in malnutrition-associated steatohepatitis and provides an overview of the available approaches for treating this condition.

Gut-Gonad Perturbations in Type-1 Diabetes Mellitus: Role of Dysbiosis, Oxidative Stress, Inflammation and Energy-Dysbalance

Type 1 diabetes mellitus is a major metabolic disorder that affects people of all age groups throughout the world. It is responsible for the alterations in male gonadal physiology in experimental models as well as in clinical cases. On the other side, diabetes mellitus has also been associated with perturbations in the gut physiology and microbiota dysbiosis. The accumulating evidence suggests a link between the gut and gonad as evident from the i) experimental data providing insights into type 1 diabetes mellitus induced gut perturbations, ii) link of gut physiology with alterations of testicular health, iii) role of gut microbiota in androgen metabolism in the intestine, and iv) epidemiological evidence linking type 1 diabetes mellitus with inflammatory bowel disease and male infertility. Considering all the pieces of evidence, it is summarized that gut dysbiosis, oxidative stress, inflammation and energy dys-balance are the prime factors involved in the gonadal damage under type 1 diabetes mellitus, in which the gut contributes significantly. Identification of novel biomarkers and intervention of suitable agents targeting these prime factors may be a step forward to restore the gonadal damage in diabetic conditions.

Development and external validation of a diagnostic model for cardiometabolic-based chronic disease : results from the China health and retirement longitudinal study (CHARLS)

BACKGROUND

Cardiovascular disease(CVD) is the leading cause of death in the world. Cardiometabolic-based chronic disease (CMBCD) model is presented that provides a basis for sustainable and early, evidence-based therapeutic targeting to mitigate the ravagest and development of CVD. CMBCD include dysglycemia, hypertension, and/or dyslipidemia progressing to downstream CVD events.

OBJECTIVES

The objective of our research was to develop and externally validate a diagnostic model of CMBCD.

METHODS

Design: Multivariable logistic regression of a cohort for 9,463 participants aged at least 45 years were drawn from the 2018 wave of the China Health and Retirement Longitudinal Study (CHARLS).

SETTING

The 2018 wave of the CHARLS.

PARTICIPANTS

Diagnostic model development: Totally 6,218 participants whose individual ID < 250,000,000,000. External validation: Totally 3,245 participants whose individual ID > 250,000,000,000.

OUTCOMES

CMBCD .

RESULTS

CMBCD occurred in 25.5%(1,584/6,218)of individuals in the development data set and 26.2%(850 /3,245)of individuals in the validation data set. The strongest predictors of CMBCD were age, general health status, location of residential address, smoking, housework ability, pain, and exercise tolerance. We developed a diagnostic model of CMBCD. Discrimination was the ability of the diagnostic model to differentiate between people who with and without CMBCD. This measure was quantified by calculating the area under the receiver operating characteristic(ROC) curve(AUC).The AUC was 0.6199 ± 0.0083, 95% confidence interval(CI) = 0.60372 ~ 0.63612. We constructed a nomograms using the development database based on age, general health status, location of residential address, smoking, housework ability, pain, and exercise tolerance. The AUC was 0.6033 ± 0.0116, 95% CI = 0.58066 ~ 0.62603 in the validation data set.

CONCLUSIONS

We developed and externally validated a diagnostic model of CMBCD. Discrimination, calibration, and decision curve analysis were satisfactory.

Microvascular Skeletal-Muscle Crosstalk in Health and Disease

As an organ system, skeletal muscle is essential for the generation of energy that underpins muscle contraction, plays a critical role in controlling energy balance and insulin-dependent glucose homeostasis, as well as vascular well-being, and regenerates following injury. To achieve homeostasis, there is requirement for "cross-talk" between the myogenic and vascular components and their regulatory factors that comprise skeletal muscle. Accordingly, this review will describe the following: [a] the embryonic cell-signaling events important in establishing vascular and myogenic cell-lineage, the cross-talk between endothelial cells (EC) and myogenic precursors underpinning the development of muscle, its vasculature and the satellite-stem-cell (SC) pool, and the EC-SC cross-talk that maintains SC quiescence and localizes ECs to SCs and angio-myogenesis postnatally; [b] the vascular-myocyte cross-talk and the actions of insulin on vasodilation and capillary surface area important for the uptake of glucose/insulin by myofibers and vascular homeostasis, the microvascular-myocyte dysfunction that characterizes the development of insulin resistance, diabetes and hypertension, and the actions of estrogen on muscle vasodilation and growth in adults; [c] the role of estrogen in utero on the development of fetal skeletal-muscle microvascularization and myofiber hypertrophy required for metabolic/vascular homeostasis after birth; [d] the EC-SC interactions that underpin myofiber vascular regeneration post-injury; and [e] the role of the skeletal-muscle vasculature in Duchenne muscular dystrophy.

The Effect of Omega-3 Fatty Acids on Insulin Resistance

Insulin resistance is a critical pathophysiological process in the onset and advancement of type 2 diabetes mellitus. It is well-recognized that alterations in the metabolism of lipids and aberrant fat buildup effectively trigger the development of resistance to insulin. Adjusting one's eating habits and managing weight appropriately are crucial for treating, controlling, and reducing the risk of T2DM because obesity and a lack of physical exercise are the primary factors responsible for the worldwide rise in T2DM. Omega-3 fatty acid is one of the polyunsaturated fatty acids (PUFA) that include long-chain omega-3 fatty acids such as eicosapentaenoic acid and docosahexaenoic acid, commonly found in fish oils. Omega-3 and omega-6 polyunsaturated fatty acids (PUFAs; 3 and 6 PUFAs) are essential for human health because they serve as metabolic precursors of eicosanoids, a class of signaling molecules that are essential for controlling a body's inflammation. Since humans are unable to produce any of the omega-3 or omega-6 PUFAs, they both constitute imperative nutritional ingredients. Long-standing concerns about long-chain omega-3 fatty acids' impact on diabetes management have been supported by experimental investigations that found significant increases in fasting glucose following omega-3 fatty acid supplementation and foods rich in PUFA and omega-3 fatty acid. Cellular explanations to explain the connection between inflammation and IR include mitochondrial dysfunction, endoplasmic reticulum (ER) stress, and oxidative stress. Modifications in the lipid composition of mitochondrial membranes and/or receptor-mediated signaling may be part of the mechanism behind the activation of mitochondrial fusion by fish oil/omega-3 PUFA. The exact molecular processes by which omega-3 PUFAs control mitochondrial activity to defend against IR are still unknown.

The Protective Role of Microglial PPARα in Diabetic Retinal Neurodegeneration and Neurovascular Dysfunction

Microglial activation and subsequent pathological neuroinflammation contribute to diabetic retinopathy (DR). However, the underlying mechanisms of microgliosis, and means to effectively suppress pathological microgliosis, remain incompletely understood. Peroxisome proliferator-activated receptor alpha (PPARα) is a transcription factor that regulates lipid metabolism. The present study aimed to determine if PPARα affects pathological microgliosis in DR. In global Pparα mice, retinal microglia exhibited decreased structural complexity and enlarged cell bodies, suggesting microglial activation. Microglia-specific conditional Pparα^-/- (PCKO) mice showed decreased retinal thickness as revealed by optical coherence tomography. Under streptozotocin (STZ)-induced diabetes, diabetic PCKO mice exhibited decreased electroretinography response, while diabetes-induced retinal dysfunction was alleviated in diabetic microglia-specific Pparα-transgenic (PCTG) mice. Additionally, diabetes-induced retinal pericyte loss was exacerbated in diabetic PCKO mice and alleviated in diabetic PCTG mice. In cultured microglial cells with the diabetic stressor 4-HNE, metabolic flux analysis demonstrated that Pparα ablation caused a metabolic shift from oxidative phosphorylation to glycolysis. Pparα deficiency also increased microglial STING and TNF-α expression. Taken together, these findings revealed a critical role for PPARα in pathological microgliosis, neurodegeneration, and vascular damage in DR, providing insight into the underlying molecular mechanisms of microgliosis in this context and suggesting microglial PPARα as a potential therapeutic target.

Chronic Antihyperglycemic Effect Exerted by Traditional Extracts of Three Mexican Medicinal Plants

Chronic hyperglycemia, the product of uncontrolled diabetes, leads to the appearance of vascular complications that can result in the premature death of diabetic patients. Consequently, pharmacological intervention with hypoglycemic agents could delay these complications and improve the quality of life of patients in the long term. Traditional Mexican medicine provides a great wealth of medicinal plants that are used for the treatment of type 2 diabetes, the most prevalent form of diabetes, accounting for nearly 90–95% of total cases. However, there is still a lack of studies that support their hypoglycemic effects, clarify their mechanisms of action, and report their long-term efficacy. Therefore, the aim of this study was to evaluate the chronic effects of the traditional extracts of some Mexican medicinal plants used by diabetic patients (Ageratina petiolaris (Moc. & Sessé ex DC.) R.M. King & H. Rob. (Asteraceae), Calea urticifolia (Mill.) DC. (Asteraceae), and Eryngium cymosum F.Delaroche (Apiaceae)) on hyperglycemia and hypertriglyceridemia. To achieve this goal, the aqueous extracts of these plants at their traditional doses were administered daily to streptozotocin-nicotinamide (STZ-NA) hyperglycemic Wistar rats for 42 days to assess their effects on nonfasting blood glucose (NFBG), glycated hemoglobin (HbA1c), and blood triglycerides (TG). The results showed that the A. petiolaris extract significantly reduced NFBG by 33% compared to its baseline (p = 0.0281). Besides, it prevented the increase in HbA1c by 2.63% (p = 0.0303) and diminished the AUC of TG (p = 0.0031) compared with the negative control. On the other hand, both C. urticifolia and E. cymosum prevented worsening of hyperglycemia by avoiding the significant increase in glucose levels seen in the negative control and the rise in HbA1c by 2.58% (p = 0.0156). These outcomes provide evidence for the first time of the antihyperglycemic effect of these Mexican medicinal plants, confirming their long-term efficacy in the control of chronic hyperglycemia.

Glucagon, cyclic AMP, and hepatic glucose mobilization: A half‐century of uncertainty

For at least 50 years, the prevailing view has been that the adenylate cyclase (AC)/cyclic AMP (cAMP)/protein kinase A pathway is the predominant signal mediating the hepatic glucose‐mobilizing actions of glucagon. A wealth of evidence, however, supports the alternative, that the operative signal most of the time is the phospholipase C (PLC)/inositol‐phosphate (IP3)/calcium/calmodulin pathway. The evidence can be summarized as follows: (1) The consensus threshold glucagon concentration for activating AC ex vivo is 100 pM, but the statistical hepatic portal plasma glucagon concentration range, measured by RIA, is between 28 and 60 pM; (2) Within that physiological concentration range, glucagon stimulates the PLC/IP3 pathway and robustly increases glucose output without affecting the AC/cAMP pathway; (3) Activation of a latent, amplified AC/cAMP pathway at concentrations below 60 pM is very unlikely; and (4) Activation of the PLC/IP3 pathway at physiological concentrations produces intracellular effects that are similar to those produced by activation of the AC/cAMP pathway at concentrations above 100 pM, including elevated intracellular calcium and altered activities and expressions of key enzymes involved in glycogenolysis, gluconeogenesis, and glycogen synthesis. Under metabolically stressful conditions, as in the early neonate or exercising adult, plasma glucagon concentrations often exceed 100 pM, recruiting the AC/cAMP pathway and enhancing the activation of PLC/IP3 pathway to boost glucose output, adaptively meeting the elevated systemic glucose demand. Whether the AC/cAMP pathway is consistently activated in starvation or diabetes is not clear. Because the importance of glucagon in the pathogenesis of diabetes is becoming increasingly evident, it is even more urgent now to resolve lingering uncertainties and definitively establish glucagon’s true mechanism of glycemia regulation in health and disease.

Metabolic Syndrome and β-Oxidation of Long-Chain Fatty Acids in the Brain, Heart, and Kidney Mitochondria

We present evidence that metabolic syndrome (MetS) represents the postreproductive stage of the human postembryonic ontogenesis. Accordingly, the genes governing this stage experience relatively weak evolutionary selection pressure, thus representing the metabolic phenotype of distant ancestors with β-oxidation of long-chain fatty acids (FAs) as the primary energy source. Mitochondria oxidize at high-rate FAs only when succinate, glutamate, or pyruvate are present. The heart and brain mitochondria work at a wide range of functional loads and possess an intrinsic inhibition of complex II to prevent oxidative stress at periods of low functional activity. Kidney mitochondria constantly work at a high rate and lack inhibition of complex II. We suggest that in people with MetS, oxidative stress is the central mechanism of the heart and brain pathologies. Oxidative stress is a secondary pathogenetic mechanism in the kidney, while the primary mechanisms are kidney hypoxia caused by persistent hyperglycemia and hypertension. Current evidence suggests that most of the nongenetic pathologies associated with MetS originate from the inconsistencies between the metabolic phenotype acquired after the transition to the postreproductive stage and excessive consumption of food rich in carbohydrates and a sedentary lifestyle.

Anti-Inflammatory Nutrients and Obesity-Associated Metabolic-Inflammation: State of the Art and Future Direction

Growing evidence supports the hypothesis that dietary factors may play a role in systemic low-grade chronic inflammation. Summary evidence from randomized controlled trials has shown substantial effects on biomarkers of inflammation following the adoption of plant-based diets (including, but not limited to, the Mediterranean diet), while consistent findings have been reported for higher intakes of whole grains, fruits, and vegetables and positive trends observed for the consumption of legumes, pulses, nuts, and olive oil. Among animal food groups, dairy products have been shown to have the best benefits on biomarkers of inflammation, while red meat and egg have been shown to have neutral effects. The present review provides an overview of the mechanisms underlying the relation between dietary factors and immune system, with a focus on specific macronutrient and non-nutrient phytochemicals (polyphenols) and low-grade inflammation. Substantial differences within each macronutrient group may explain the conflicting results obtained regarding foods high in saturated fats and carbohydrates, underlying the role of specific subtypes of molecules (i.e., short-chain fatty acids or fiber vs. long chain fatty acids or free added sugars) when exploring the relation between diet and inflammation, as well as the importance of the food matrix and the commixture of foods in the context of whole dietary patterns. Dietary polyphenols and oligopeptides have been hypothesized to exert several functions, including the regulation of the inflammatory response and effects on the immune system. Overall, evidence suggests that dietary factors may affect the immune system regardless of obesity-related inflammation.

Risk Factors Analysis and Management of Cardiometabolic-Based Chronic Disease in Low- and Middle-Income Countries

The epidemic of obesity or adiposity-based chronic diseases presents a significant challenge with the rising prevalence of morbidities and mortality due to atherosclerotic cardiovascular diseases (ASCVD), especially in low- and middle-income countries (LMIC). The underlying pathophysiology of metabolic inflexibility is a common thread linking insulin resistance to cardiometabolic-based chronic disease (CMBCD), including dysglycemia, hypertension, and dyslipidemia progressing to downstream ASCVD events. The complex CMBCD paradigm in the LMIC population within the socio-economic and cultural context highlights considerable heterogeneity of disease predisposition, clinical patterns, and socio-medical needs. This review intends to summarize the current knowledge of CMBCD. We describe recently established or emerging trends for managing risk factors, assessment tools for evaluating ASCVD risk, and various pharmacological and non-pharmacological measures particularly relevant for LMICs. A CMBCD model positions insulin resistance and β-cell dysfunction at the summit of the disease spectrum may improve outcomes at a lower cost in LMICs. Despite identifying multiple pathophysiologic disturbances constituting CMBCD, a large percentage of the patient at risk for ASCVD remains undefined. Targeting dysglycemia, dyslipidemia, and hypertension using antihypertensive, statins, anti-glycemic, and antiplatelet agents has reduced the incidence of ASCVD. Thus, primordial prevention targeting pathophysiological changes that cause abnormalities in adiposity and primary prevention by detecting and managing risk factors remains the foundation for CMBCD management. Therefore, targeting pathways that address mitochondrial dysfunction would exert a beneficial effect on metabolic inflexibility that may potentially correct insulin resistance, β cell dysfunction and, consequently, would be therapeutically effective across the entire continuum of CMBCD.

TRC150094, a Novel Mitochondrial Modulator, Reduces Cardio-Metabolic Risk as an Add-On Treatment: a Phase-2, 24-Week, Multi-Center, Randomized, Double-Blind, Clinical Trial

BACKGROUND

TRC150094, a novel mitochondrial modulator, reduces insulin resistance and is expected to improve the trinity of dysglycemia, dyslipidemia, and hypertension. In this multi-dose phase-2 study, we evaluated the safety and efficacy of TRC150094 in diabetic subjects with dyslipidemia receiving standard of care.

METHODS

A randomized, multicenter, double-blind, placebo-controlled, parallel-group, Phase 2 study was conducted in 225 subjects from July 2013 to August 2015. The key inclusion criteria were body mass index of 23-35 kg/m², age between 30 and 65 years, fasting glucose of ≥126 or glycated hemoglobin (HbA1c) of ≥6.4% stabilized on treatment with ≤2 oral hypoglycemic agents, apolipoprotein-B (apo-B) ≥100 mg/dL, serum triglyceride (TG) ≥150 mg/dL, systolic blood pressure (SBP) ≥130 mmHg, and diastolic blood pressure (DBP) ≥85 mmHg with/without antihypertensive treatment. The subjects were randomly assigned to one of three TRC150094 doses (25, 50, or 75 mg) or placebo for 24 weeks. The outcomes assessed included fasting plasma glucose (FPG), insulin, mean arterial blood pressure (MAP), and apoB. In addition, safety and tolerability were assessed.

RESULTS

A reduction for dose up to 50 mg was noted for FPG in the range of 13.9 to 21.7 mg/dL (p < 0.05 for TRC150094 25 and 50 mg), fasting insulin reduction in the range 2.7 to 6.0 mU/L (all doses, p > 0.05), and improved HOMA-IR (-2.0 to -2.5) (all doses, p > 0.05) compared to placebo after 24 weeks of treatment. Furthermore, a significant reduction in MAP in the range 3.1 to 4.2 mmHg (p < 0.05 for TRC150094 25 and 75 mg) was noted. In addition, TRC150094 treatment was weight neutral, had a favorable effect on lowering atherogenic lipid fractions, including non-HDL cholesterol (-6.8 mg/dL at 50 mg dose). Adverse events were mild to moderate in nature and not dose-related. One adverse event not related to treatment led to the discontinuation of the study. Overall, TRC150094 was safe and well tolerated for up to 24 weeks.

CONCLUSION

In this study, TRC150094 treatment in the dose range of 25 to 50 mg showed improvement in various components of CMBCD, ie, dysglycemia, dyslipidemia, and hypertension.

TRIAL REGISTRATION

This study was registered in the Clinical Trial Registry of India. Trial registration number: CTRI/2013/03/003444. Date of registration: 4th March 2013.

Eating Slowly Is Associated with Undernutrition among Community-Dwelling Adult Men and Older Adult Women

The double burden of malnutrition refers to the co-occurrence of overweight and obesity and undernutrition. Eating quickly has been linked to overweight and obesity. However, no study has examined the association between eating speed and undernutrition. This retrospective, cross-sectional study analyzed data from 3529 community-dwelling residents. Eating speed was divided into three categories: fast, medium, and slow. Undernutrition was defined as body mass index (BMI) of <18.5 kg/m² in adults aged < 70 years (adults) and as <20 kg/m² in adults aged ≥ 70 years (older adults), in accordance with the Global Leadership Initiative on Malnutrition criteria for Asians. Multivariable logistic regression analysis was used to examine the association between eating speed and undernutrition. Among adult men, compared with eating quickly, eating slowly was associated with elevated prevalence of undernutrition (odds ratio (OR) 9.68, 95% confidence interval (CI) 2.32–40.51, p = 0.001). Among older adult women, the prevalence of undernutrition in the slow-eating group was higher than that in the fast-eating group (OR 3.82, 95% Cl 1.51–9.69, p = 0.005). Eating slowly is independently associated with the prevalence of undernutrition among community-dwelling adult men and older adult women in Japan.

Safety, Tolerability, and Pharmacokinetics of a Novel Mitochondrial Modulator, TRC150094, in Overweight and Obese Subjects: A Randomized Phase-I Clinical Trial

TRC150094, a novel mitochondrial modulator, can restore metabolic flexibility by improving insulin resistance in preclinical studies. This study primarily aims to evaluate the safety, tolerability, and pharmacokinetics (PK) of oral TRC150094 after conducting two double-blind, randomized, Phase-I studies, single ascending dose (SAD) and multiple ascending dose (MAD), with n = 46, in overweight/obese adult and elderly subjects. In addition, the effect of TRC150094 on pharmacodynamic (PD) efficacy markers was evaluated. PK assessments, including maximum concentration (Cmax), area under the plasma concentration (AUC), time to Cmax (Tmax), and elimination half-life (t½), were assessed at pre-specified time points. PD assessments included apolipoprotein B (ApoB), triglycerides, hepatic fat by magnetic resonance spectroscopy (MRS) and cardiopulmonary exercise testing (CPET) parameters. TRC150094 was rapidly absorbed, and the AUC of TRC150094 increased in a dose-dependent manner across all doses in non-elderly and elderly cohorts. Cmax was more than the dose-proportional for all doses in all cohorts. Tmax ranged from 0.25 to 4 h, and t½ ranged from 15 to 18 h, making TRC150094 suitable for once-daily dosing. Food did not interfere with the overall absorption of the drug. The metabolites of TRC150094 were glucuronide and sulfate conjugates, and 20% of the drug was excreted unchanged in the urine. TRC150094 at 50 mg showed an improving trend in triglycerides. A significant reduction in Apo B was observed after 50 mg dose (-2.34 vs. 13.24%, p = 0.008), which was, however, not the case after 150 mg (8.78 vs. 13.24%, p = 0.1221). Other parameters such as hepatic fat and insulin sensitivity indices (HOMA-IR, MATSUDA Index derived from OGTT) showed an improving trend for the dose of 50 mg. In terms of safety, all the AEs reported were mild to moderate in severity. None of the adverse events was considered definitely or probably related to treatment, and there were no abnormal laboratory findings. In conclusion, the PK of TRC150094 was linear with no clinically significant food effect. TRC150094 and its metabolites suggest a lesser likelihood of drug-drug interactions. Overall, TRC150094 ensured safety and exhibited suitability for all subjects. Clinical Trial Registration: EUDRA CT: 2009-014941-10 (SAD) and CTR-India registration: CTRI/2009/091/000601 (MAD).