The role of oxidative stress in diabetes mellitus-induced vascular endothelial dysfunction

Impact of Diabetic Condition on the Remodeling of In Situ Tissue-Engineered Heart Valves

Most in situ tissue-engineered heart valve (TEHV) evaluation studies are conducted in a healthy physical environment, which cannot accurately reflect the specific characteristics of patients. In this study, we established a diabetic rabbit model and implanted decellularized extracellular matrix (dECM) into the abdominal aorta of rabbits through interventional surgery with a follow-up period of 8 weeks. The results indicated that dECM implants in diabetic rabbits exhibited poorer endothelialization and more severe fibrosis compared to those in healthy animals. Furthermore, mechanistic studies revealed that high glucose induced endothelial cell (EC) apoptosis and impeded their proliferation and migration, accompanied by an increase in reactive oxygen species (ROS) concentration and a decrease in the nitric oxide (NO) level. High glucose also led to elevated ROS levels and an increased expression of inflammatory factors and transforming growth factor β1 (TGF-β1) in macrophages, contributing to fibrosis. These findings suggest that oxidative-stress-mediated mechanisms are likely the primary pathways affecting heart valve repair and regeneration under diabetic conditions. Therefore, future design and evaluation of TEHVs may concern more patient-specific circumstances.

Association between fibrosis-4 index and cognitive impairment in elderly patients with hypertension: A cross-sectional study

The fibrosis-4 index (FIB-4) is a noninvasive fibrosis test that is recommended for patients who are at risk of developing hepatic fibrosis. The aim of the study was to explore the correlation between FIB-4 index and the decline of cognitive function among older patients with hypertension. The study used a cross-sectional design to analyze data obtained from the NHANES 2011-2014. The significance of the FIB-4 index correlation with cognitive function in individuals over the age of 60 was evaluated via multivariate regression models. The nonlinear link was described and fitted smoothed curves. There were a total of 2039 participants in the study, and those with a higher FIB-4 index were more susceptible to developing cognitive decline. In the completely adjusted model, the association remained statistically significant between the FIB-4 index and poor cognitive function as measured by CERAD: Total Score (OR = 0.72, 0.57-0.91), Animal Fluency Score (OR = 0.66, 0.48-0.91), and Digit Symbol Score (OR = 0.36, 0.17-0.77). A nonlinear association was found between the FIB-4 and poor cognitive ability: Total Score, CERAD: Score Delayed Recall, Digit Symbol Score, and Animal Fluency Score. In elderly patients with hypertension, a high FIB-4 index is correlated with an increased prevalence of cognitive decline. Hence, the FIB-4 index could potentially serve as a valuable tool for determining individuals with hypertension who are susceptible to both liver-related complications and cognitive impairment.

Impact of apoptosis and oxidative stress on pancreatic beta cell pathophysiology in streptozotocin-induced Type 1 diabetes mellitus

AIMS

Hyperglycemia plays a crucial role in the islet cells, especially pancreatic beta cell death in type 1 diabetes mellitus (T1DM). However, a few research have concentrated on the pathophysiology of apoptosis and oxidative stress in T1DM. The aim of this study was to determine the expression of Caspase 3, Caspase 9, 8-OHdG, Glutathione Reductase, endothelial and inducible nitric oxide synthase in the pancreatic tissue of streptozotocin (STZ)-induced T1DM patients and to compare the cellular mechanisms underlying this metabolic disorder.

METHODS

For this purpose, a total of 20 Wistar albino rats were divided into two groups: Control (C) and Diabetes Mellitus (DM). In the DM group, T1DM was induced by STZ. Rats in the C group were injected intravenously with buffer solution. At the end of the day 20, rats were necropsied and immunohistochemical procedures were applied.

RESULTS

The immunohistochemical examination revealed, strong positive immunoreactions were observed in the islet cells of the DM groups, particularly when all antibody stains were considered. On the other hand, the C groups showed minimal changes. The difference between the C and DM groups in terms of all antibodies was statistically significant (p<0.01).

CONCLUSIONS

In the present study, it was concluded that apoptosis, oxidative stress and NOS expressions were involved in islet cell destruction in pancreatic tissue in STZ-induced T1DM.

KIAA0753 enhances osteoblast differentiation suppressed by diabetes

Diabetes-related bone loss represents a significant complication that persistently jeopardizes the bone health of individuals with diabetes. Primary cilia proteins have been reported to play a vital role in regulating osteoblast differentiation in diabetes-related bone loss. However, the specific contribution of KIAA0753, a primary cilia protein, in bone loss induced by diabetes remains unclear. In this investigation, we elucidated the pivotal role of KIAA0753 as a promoter of osteoblast differentiation in diabetes. RNA sequencing demonstrated a marked downregulation of KIAA0753 expression in pro-bone MC3T3 cells exposed to a high glucose environment. Diabetes mouse models further validated the downregulation of KIAA0753 protein in the femur. Diabetes was observed to inhibit osteoblast differentiation in vitro, evidenced by downregulating the protein expression of OCN, OPN and ALP, decreasing primary cilia biosynthesis, and suppressing the Hedgehog signalling pathway. Knocking down KIAA0753 using shRNA methods was found to shorten primary cilia. Conversely, overexpression KIAA0753 rescued these changes. Additional insights indicated that KIAA0753 effectively restored osteoblast differentiation by directly interacting with SHH, OCN and Gli2, thereby activating the Hedgehog signalling pathway and mitigating the ubiquitination of Gli2 in diabetes. In summary, we report a negative regulatory relationship between KIAA0753 and diabetes-related bone loss. The clarification of KIAA0753's role offers valuable insights into the intricate mechanisms underlying diabetic bone complications.

A systematic review and meta-analysis of ischemia-modified albumin in diabetes mellitus

Aim

There is an ongoing search for novel biomarkers of diabetes. We conducted a systematic review and meta-analysis of the serum concentrations of ischemia-modified albumin (IMA), a candidate biomarker of oxidative stress, acidosis, and ischemia, in patients with pre-diabetes, different types of diabetes mellitus (type 1, T1DM, type 2, T2DM, and gestational, GDM), and healthy controls.

Methods

We searched for case-control studies published in PubMed, Web of Science, and Scopus from inception to December 31, 2023. The risk of bias and the certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist and GRADE, respectively.

Results

In 29 studies, T2DM patients had significantly higher IMA concentrations when compared to controls (standard mean difference, SMD = 1.83, 95 % CI 1.46 to 2.21, p˂0.001; I2 = 95.7 %, p < 0.001; low certainty of evidence). Significant associations were observed between the SMD and glycated hemoglobin (p = 0.007), creatinine (p = 0.003), triglycerides (p = 0.029), and the presence of diabetes complications (p = 0.003). Similar trends, albeit in a smaller number of studies, were observed in T1DM (two studies; SMD = 1.59, 95 % CI -0.09 to 3.26, p˂0.063; I2 = 95.8 %, p < 0.001), GDM (three studies; SMD = 3.41, 95 % CI 1.14 to 5.67, p = 0.003; I2 = 97.0 %, p < 0.001) and pre-diabetes (three studies; SMD = 15.25, 95 % CI 9.86 to 20.65, p˂0.001; I2 = 99.3 %, p < 0.001).

Conclusion

Our study suggests that IMA is a promising biomarker for determining the presence of oxidative stress, acidosis, and ischemia in pre-diabetes and T1DM, T2DM, and GDM. However, the utility of measuring circulating IMA warrants confirmation in prospective studies investigating clinical endpoints in pre-diabetes and in different types of diabetes (PROSPERO registration number: CRD42024504690).

Association of dietary antioxidant intake with depression risk and all-cause mortality in people with prediabetes

People with diabetes has an elevated risk of depression, and depression contributes to a worse prognosis for people with diabetes. Dietary antioxidants have been shown to reduce the risk of depression in the general population. Therefore, we hypothesized that dietary antioxidants would also help to reduce the risk of depression and all-cause mortality in people with prediabetes. A total of 8789 participants aged 20 years and older from the 2005-2018 National Health and Nutrition Examination Surveys who met the diagnostic criteria for prediabetes were included in our study. The associations between six dietary antioxidant intakes and the composite dietary antioxidant index (CDAI) with depression risk and all-cause mortality were assessed using weighted logistic and Cox regression. Possible nonlinear associations were further explored using restricted cubic spline. To ensure the reliability of the findings, the multiple imputations by chained equation were applied to missing covariates to avoid potential bias. Our study found that moderate dietary antioxidant intake prevents depression and improves prognosis in people with prediabetes. Moreover, a CDAI score near three allows for maximum benefit. Our findings could provide clues for early intervention in people with diabetes.

Association between stress hyperglycemia ratio and all-cause mortality in critically ill patients with atrial fibrillation: insights from a MIMIC-IV study

Background

The stress hyperglycemia ratio (SHR) has emerged as a potential prognostic indicator for various critical illnesses. However, its role in determining outcomes in patients with atrial fibrillation (AF) within the intensive care unit (ICU) remains unclear. This study aimed to elucidate the association between SHR and all-cause mortality in this clinical setting.

Methods

We conducted a retrospective cohort study utilizing data from a large, retrospective database. Critically ill patients with documented AF were stratified based on quartiles of SHR. The primary outcome was 365-day all-cause mortality, with secondary outcomes including 90-day and 28-day mortality. COX proportional hazards models adjusted for confounders and Kaplan-Meier curve analyses were used to explore the relationship between SHR and mortality.

Results

2,679 patients with critical AF were enrolled in the final study. Among the patients studied, those in the highest SHR quartiles exhibited an increased risk of 365-day all-cause mortality (HR:1.32, 95%CI=1.06-1.65). Notably, in subgroup analyses, the prognostic value of SHR was particularly pronounced in patients with hypertension. Sensitivity analyses confirmed the persistence of these findings after excluding cohorts with malignant tumors, and heart failure.

Conclusions

Our research discerns a positive association between SHR and all-cause mortality in critically ill patients with AF, highlighting the significance of acute glycemic dysregulation on patient outcomes. Longer follow-up is still needed in the future to study the association between SHR and all-cause mortality in critically ill patients with AF.

mTOR Dysregulation, Insulin Resistance, and Hypertension

Worldwide, diabetes mellitus (DM) and cardiovascular diseases (CVDs) represent serious health problems associated with unhealthy diet and sedentarism. Metabolic syndrome (MetS) is characterized by obesity, dyslipidemia, hyperglycemia, insulin resistance (IR) and hypertension. The mammalian target of rapamycin (mTOR) is a serine/threonine kinase with key roles in glucose and lipid metabolism, cell growth, survival and proliferation. mTOR hyperactivation disturbs glucose metabolism, leading to hyperglycemia and further to IR, with a higher incidence in the Western population. Metformin is one of the most used hypoglycemic drugs, with anti-inflammatory, antioxidant and antitumoral properties, having also the capacity to inhibit mTOR. mTOR inhibitors such as rapamycin and its analogs everolimus and temsirolimus block mTOR activity, decrease the levels of glucose and triglycerides, and reduce body weight. The link between mTOR dysregulation, IR, hypertension and mTOR inhibitors has not been fully described. Therefore, the main aim of this narrative review is to present the mechanism by which nutrients, proinflammatory cytokines, increased salt intake and renin-angiotensin-aldosterone system (RAAS) dysregulation induce mTOR overactivation, associated further with IR and hypertension development, and also mTOR inhibitors with higher potential to block the activity of this protein kinase.

Effects of Ginger (Zingiber officinale) on the Hallmarks of Aging

Ginger (Zingiber officinale Roscoe) is broadly used as a traditional remedy and food ingredient, and numerous preclinical and clinical studies have demonstrated health benefits in a range of age-related disorders. Moreover, longevity-promoting effects have been demonstrated in several (preclinical) research models. With this work, we aimed to comprehensively review the reported effects of ginger and its bioactive constituents on the twelve established hallmarks of aging, with the ultimate goal of gaining a deeper understanding of the potential for future interventions in the area of longevity-extension and counteracting of aging-related diseases. The reviewed literature supports the favorable effects of ginger and some of its constituents on all twelve hallmarks of aging, with a particularly high number of animal research studies indicating counteraction of nutrient-sensing dysregulations, mitochondrial dysfunction, chronic inflammation, and dysbiosis. On this background, validation in human clinical trials is still insufficient or is entirely missing, with the exception of some studies indicating positive effects on deregulated nutrient-sensing, chronic inflammation, and dysbiosis. Thus, the existing body of literature clearly supports the potential of ginger to be further studied in clinical trials as a supplement for the promotion of both lifespan and health span.

Causal Effects of Oxidative Stress on Diabetes Mellitus and Microvascular Complications: Insights Integrating Genome-Wide Mendelian Randomization, DNA Methylation, and Proteome

BACKGROUND

Oxidative stress (OS) is involved in the development of diabetes, but the genetic mechanisms are not completely understood. We integrated multi-omics data in order to explore the genetic relations between OS-related genes, diabetes mellitus, and microvascular complications using Mendelian randomization and colocalization analysis.

METHODS

Summary-level data related to OS were acquired from respective studies of methylation, expression, and protein abundance quantitative trait loci. Genetic associations concerning diabetes, diabetic nephropathy (DN), and diabetic retinopathy (DR) were derived from the FinnGen study. Summary-data-based Mendelian randomization (SMR) analysis was conducted to evaluate the correlations between molecular features concerned with OS-related genes and diabetes mellitus, along with its microvascular complications. Additionally, we performed colocalization analysis to determine if the detected signal pairs shared a causal genetic variant.

RESULTS

At the genetic level, we identified ten potential causal associations of oxidative stress genes with diabetes, along with microvascular complications, through SMR and colocalization analysis. After integrating the DNA methylation quantitative trait loci (mQTL) and expression QTL (eQTL) data, our analyses revealed a correlation between the methylation site cg26343298 and reduced expression of TP53INP1, supporting the protective role of cg26343298 methylation on type 2 diabetes (T2D) and diabetic nephropathy. Similarly, an inverse association was observed between gene methylation and expression in CHEK1 (cg07110182), confirming the beneficial effect of modification of CHEK1 by cg07110182 in diabetic retinopathy. In addition, upregulation of SUOX expression by cg22580629 was linked to a reduced risk of diabetic retinopathy. At circulating protein levels, genetically predicted a higher level of ICAM1 (OR 1.05, 95%CI 1.03-1.08) was positively connected with the risk of diabetic retinopathy.

CONCLUSIONS

This SMR study elucidated that the TP53INP1 gene was putatively associated with T2D and DN risk, while the SUOX and CHEK1 genes were associated with DR risk through oxidative stress mechanisms. Additionally, our study showed a positive correlation between the ICAM-1 protein and DR. These findings may enhance our understanding of their pathogenesis and suggest new therapeutic targets for clinical practice.

Sex differences in clinical profile, left ventricular remodeling and cardiovascular outcomes among diabetic patients with heart failure and reduced ejection fraction: a cardiac-MRI-based study

BACKGROUND

Heart failure with reduced ejection fraction (HFrEF) is associated with a high rate of mortality and morbidity. Evidence has shown that sex differences may be an important contributor to phenotypic heterogeneity in patients with HFrEF. Although diabetes mellitus (DM) frequently coexists with HFrEF and results in a worse prognosis, there remains a need to identify sex-related differences in the characteristics and outcomes of this population. In this study, we aimed to investigate the between-sex differences in clinical profile, left ventricular (LV) remodeling, and cardiovascular risk factors and outcomes in patients with HFrEF concomitant with DM.

METHODS

A total of 273 patients with HFrEF concomitant with DM who underwent cardiac MRI were included in this study. Clinical characteristics, LV remodeling as assessed by cardiac MRI, and cardiovascular risk factors and outcomes were compared between sexes.

RESULTS

Women were older, leaner and prone to have anemia and hypoproteinemia but less likely to have ischemic etiology. Cardiac MRI revealed that despite similar LVEFs between the sexes, there was more LV concentric remodeling, less impaired global systolic peak strain in longitudinal and circumferential components and a decreased likelihood of late gadolinium enhancement presence in women than in men. During a median follow-up time of 34.6 months, women exhibited better overall survival than men did (log-rank P = 0.042). Multivariable Cox proportional hazards analysis indicated different risk factors for predicting outcomes between sexes, with hypertension [hazard ratio (HR) = 2.05, 95% confidence interval (CI) 1.05 to 4.85, P = 0.041] and hypoproteinemia (HR = 2.27, 95% CI 1.06 to 4.37, P = 0.039) serving as independent determinants of outcomes in women, whereas ischemic etiology (HR = 1.96, 95% CI 1.11 to 3.48, P = 0.021) and atrial fibrillation (HR = 1.86, 95% CI 1.02 to 3.41, P = 0.044) served as independent determinants of outcomes in men.

CONCLUSIONS

Among patients with HFrEF concomitant with DM, women displayed different LV remodeling and risk factors and had better survival than men did. Sex-based phenotypic heterogeneity in patients with HFrEF in the context of DM should be addressed in clinical practice.

Associations between serum albumin level trajectories and clinical outcomes in sepsis patients in ICU: insights from longitudinal group trajectory modeling

Background

Sepsis triggers a strong inflammatory response, often leading to organ failure and high mortality. The role of serum albumin levels in sepsis is critical but not fully understood, particularly regarding the significance of albumin level changes over time. This study utilized Group-based Trajectory Modeling (GBTM) to investigate the patterns of serum albumin changes and their impact on sepsis outcomes.

Methods

We conducted a retrospective analysis on ICU patients from West China Hospital (2015-2022), employing GBTM to study serum albumin fluctuations within the first week of ICU admission. The study factored in demographics, clinical parameters, and comorbidities, handling missing data through multiple imputation. Outcomes assessed included 28-day mortality, overall hospital mortality, and secondary complications such as AKI and the need for mechanical ventilation.

Results

Data from 1,950 patients revealed four serum albumin trajectories, showing distinct patterns of consistently low, increasing, moderate, and consistently high levels. These groups differed significantly in mortality, with the consistently low level group experiencing the highest mortality. No significant difference in 28-day mortality was observed among the other groups. Subgroup analysis did not alter these findings.

Conclusion

The study identified four albumin trajectory groups in sepsis patients, highlighting that those with persistently low levels had the worst outcomes, while those with increasing levels had the best. Stable high levels above 30 g/L did not change outcomes significantly. These findings can inform clinical decisions, helping to identify high-risk patients early and tailor treatment approaches.

Diabetes Mellitus in Non-Functioning Adrenal Incidentalomas: Analysis of the Mild Autonomous Cortisol Secretion (MACS) Impact on Glucose Profile

Non-functioning adrenal incidentalomas (NFAIs) have been placed in relationship with a higher risk of glucose profile anomalies, while the full-blown typical picture of Cushing's syndrome (CS) and associated secondary (glucocorticoid-induced) diabetes mellitus is not explicitly confirmed in this instance. Our objective was to highlight the most recent data concerning the glucose profile, particularly, type 2 diabetes mellitus (T2DM) in NFAIs with/without mild autonomous cortisol secretion (MACS). This was a comprehensive review of the literature; the search was conducted according to various combinations of key terms. We included English-published, original studies across a 5-year window of publication time (from January 2020 until 1 April 2024) on PubMed. We excluded case reports, reviews, studies on T1DM or secondary diabetes, and experimental data. We identified 37 studies of various designs (14 retrospective studies as well 13 cross-sectional, 4 cohorts, 3 prospective, and 2 case-control studies) that analysed 17,391 individuals, with a female-to-male ratio of 1.47 (aged between 14 and 96 years). T2DM prevalence in MACS (affecting 10 to 30% of NFAIs) ranged from 12% to 44%. The highest T2DM prevalence in NFAI was 45.2% in one study. MACS versus (non-MACS) NFAIs (n = 16) showed an increased risk of T2DM and even of prediabetes or higher fasting plasma glucose or HbA1c (no unanimous results). T2DM prevalence was analysed in NFAI (N = 1243, female-to-male ratio of 1.11, mean age of 60.42) versus (non-tumour) controls (N = 1548, female-to-male ratio of 0.91, average age of 60.22) amid four studies, and two of them were confirmatory with respect to a higher rate in NFAIs. Four studies included a sub-group of CS compared to NFAI/MACS, and two of them did not confirm an increased rate of glucose profile anomalies in CS versus NFAIs/ACS. The longest period of follow-up with concern to the glycaemic profile was 10.5 years, and one cohort showed a significant increase in the T2DM rate at 17.9% compared to the baseline value of 0.03%. Additionally, inconsistent data from six studies enrolling 1039 individuals that underwent adrenalectomy (N = 674) and conservative management (N = 365) pinpointed the impact of the surgery in NFAIs. The regulation of the glucose metabolism after adrenalectomy versus baseline versus conservative management (n = 3) was improved. To our knowledge, this comprehensive review included one of the largest recent analyses in the field of glucose profile amid the confirmation of MACS/NFAI. In light of the rising incidence of NFAI/AIs due to easier access to imagery scans and endocrine evaluation across the spectrum of modern medicine, it is critical to assess if these patients have an increased frequency of cardio-metabolic disorders that worsen their overall comorbidity and mortality profile, including via the confirmation of T2DM.

Enhancing endothelial colony-forming cells for treating diabetic vascular complications: challenges and clinical prospects

Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia, leading to various vascular complications. Accumulating evidence indicates that endothelial colony-forming cells (ECFCs) have attractive prospects for repairing and restoring blood vessels. Thus, ECFCs may be a novel therapeutic option for diabetic patients with vascular complications who require revascularization therapy. However, it has been reported that the function of ECFCs is impaired in DM, which poses challenges for the autologous transplantation of ECFCs. In this review, we summarize the molecular mechanisms that may be responsible for ECFC dysfunction and discuss potential strategies for improving the therapeutic efficacy of ECFCs derived from patients with DM. Finally, we discuss barriers to the use of ECFCs in human studies in light of the fact that there are no published reports using these cells in humans.

Effect of early endothelial function improvement on subclinical target organ damage in hypertensives

Endothelial dysfunction is acknowledged as a marker for subclinical target organ damage (STOD) in hypertension, though its therapeutic potential has not yet been clarified. This study assessed whether early endothelial function improvement (EEFI) reduced STOD in patients with essential hypertension (EH). We conducted a retrospective cohort analysis of 456 EH patients initially free from STOD. Endothelial function was assessed using brachial artery flow-mediated dilation (FMD), with values ≤ 7.1% indicating dysfunction. Patients were initially categorized by endothelial status (dysfunction: n = 180, normal: n = 276), and further divided into improved or unimproved groups based on changes within three months post-enrollment. During a median follow-up of 25 months, 177 patients developed STOD. The incidence of STOD was significantly higher in patients with initial dysfunction compared to those with normal function. Kaplan-Meier analysis indicated that the improved group had a lower cumulative incidence of STOD compared to the unimproved group (p < 0.05). Multivariable Cox regression confirmed EEFI as an independent protective factor against STOD in EH patients (p < 0.05), regardless of their baseline endothelial status, especially in those under 65 years old, non-smokers, and with low-density lipoprotein cholesterol levels ≤ 3.4 mmol/L. In conclusion, EEFI significantly reduces STOD incidence in EH patients, particularly in specific subgroups, emphasizing the need for early intervention in endothelial function to prevent STOD.

Evaluating the impact of type 2 diabetes mellitus on pulmonary vascular function and the development of pulmonary fibrosis

The increasing prevalence of type 2 diabetes mellitus (T2DM) is a significant worldwide health concern caused by sedentary lifestyles and unhealthy diets. Beyond glycemic control, T2DM impacts multiple organ systems, leading to various complications. While traditionally associated with cardiovascular and microvascular complications, emerging evidence indicates significant effects on pulmonary health. Pulmonary vascular dysfunction and fibrosis, characterized by alterations in vascular tone and excessive extracellular matrix deposition, are increasingly recognized in individuals with T2DM. The onset of T2DM is often preceded by prediabetes, an intermediate hyperglycemic state that is associated with increased diabetes and cardiovascular disease risk. This review explores the relationship between T2DM, pulmonary vascular dysfunction and pulmonary fibrosis, with a focus on potential links with prediabetes. Pulmonary vascular function, including the roles of nitric oxide (NO), prostacyclin (PGI2), endothelin-1 (ET-1), thromboxane A2 (TxA2) and thrombospondin-1 (THBS1), is discussed in the context of T2DM and prediabetes. Mechanisms linking T2DM to pulmonary fibrosis, such as oxidative stress, dysregulated fibrotic signaling, and chronic inflammation, are explained. The impact of prediabetes on pulmonary health, including endothelial dysfunction, oxidative stress, and dysregulated vasoactive mediators, is highlighted. Early detection and intervention during the prediabetic stage may reduce respiratory complications associated with T2DM, emphasizing the importance of management strategies targeting blood glucose regulation and vascular health. More research that looks into the mechanisms underlying pulmonary complications in T2DM and prediabetes is needed.

Protective and curative effects of unconjugated bilirubin on gene expression of LOX-1 and iNOS in the heart of rats receiving high-fat diet and low dose streptozotocin: a histomorphometric approach

BACKGROUND

Atherosclerosis is a chronic inflammatory condition affecting the large arteries and is a major cause of cardiovascular diseases (CVDs) globally. Increased levels of adhesion molecules in cardiac tissue serve as prognostic markers for coronary artery occlusion risk. Given the antioxidant properties of bilirubin and its inverse correlation with atherosclerosis, this study aimed to assess the beneficial effects of bilirubin on atherosclerotic indices and heart structure in high-fat diet-fed diabetic rats with atherosclerosis.

METHODS

Atherosclerosis was induced in three out of five groups of adult male Sprague Dawley rats through a 14-week period of high-fat diet (HFD) consumption and a single low dose of streptozotocin (STZ) (35 mg/kg). The atherosclerotic rats were then treated with intraperitoneal administration of 10 mg/kg/day bilirubin for either 6 or 14 weeks (treated and protected groups, respectively), or the vehicle. Two additional groups served as the control and bilirubin-treated rats. Subsequently, the mRNA expression levels of vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), lectin-like LDL receptor 1 (LOX-1), and the inducible nitric oxide synthase (iNOS) were analyzed using quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Histopathological and stereological analyses were performed to assess changes in the heart structure.

RESULTS

Bilirubin significantly decreased the expression of VCAM-1, ICAM-1, LOX-1, and iNOS genes in the treated group. Moreover, bilirubin mitigated pathological damage in the left ventricle of the heart. Stereological analysis revealed a decrease in the left ventricle and myocardium volume, accompanied by an increase in vessel volume in rats treated with bilirubin.

CONCLUSION

These findings demonstrate that mild hyperbilirubinemia can protect against the progression of atherosclerosis and heart failure by improving lipid profile, modulating adhesion molecules, LOX-1, and iNOS gene expression levels.

Prediabetes Increases the Risk of Frailty in Prefrail Older Adults With Hypertension: Beneficial Effects of Metformin

BACKGROUND

Prediabetes has garnered increasing attention due to its association with cardiovascular conditions, especially hypertension, which heightens the risk of prefrailty and frailty among older individuals.

METHODS

We screened elders with prefrail hypertension from March 2021 to January 2023. We assessed the correlation linking cognitive dysfunction (Montreal Cognitive Assessment score), insulin resistance (triglyceride-to-glucose index), and physical impairment (5-meter gait speed). Then, we measured the risk of developing frailty after a 1-year follow-up period, adjusting the outcome using multivariable Cox regression analysis. We also investigated the impact of administering 500 mg of metformin once daily to a subset of frail subjects for an additional 6 months.

RESULTS

We assessed the relationship between the triglyceride-to-glucose index and the Montreal Cognitive Assessment score, observing a significant correlation (r, 0.880; P<0.0001). Similarly, we analyzed the association between the triglyceride-to-glucose index and 5-meter gait speed, uncovering a significant link between insulin resistance and physical impairment (r, 0.809; P<0.0001). Prediabetes was found to significantly (P<0.0001) elevate the risk of frailty development compared with individuals without prediabetes by the end of the 1-year follow-up, a finding confirmed via multivariable analysis with Cox regression. Furthermore, among the subgroup of subjects who developed frailty, those who received metformin exhibited a significant decrease in frailty levels (P<0.0001).

CONCLUSIONS

Insulin resistance and prediabetes play substantial roles in the development of cognitive and physical impairments, highlighting their importance in managing hypertension, even before the onset of frank diabetes. Metformin, a well-established drug for the treatment of diabetes, has shown favorable effects in mitigating frailty.

High-density lipoprotein in diabetes: Structural and functional relevance

Low levels of high-density lipoprotein-cholesterol (HDL-C) is considered a major cardiovascular risk factor. However, recent studies have suggested a more U-shaped association between HDL-C and cardiovascular disease. It has been shown that the cardioprotective effect of HDL is related to the functions of HDL particles rather than their cholesterol content. HDL particles are highly heterogeneous and have multiple functions relevant to cardiometabolic conditions including cholesterol efflux capacity, anti-oxidative, anti-inflammatory, and vasoactive properties. There are quantitative and qualitative changes in HDL as well as functional abnormalities in both type 1 and type 2 diabetes. Non-enzymatic glycation, carbamylation, oxidative stress, and systemic inflammation can modify the HDL composition and therefore the functions, especially in situations of poor glycemic control. Studies of HDL proteomics and lipidomics have provided further insights into the structure-function relationship of HDL in diabetes. Interestingly, HDL also has a pleiotropic anti-diabetic effect, improving glycemic control through improvement in insulin sensitivity and β-cell function. Given the important role of HDL in cardiometabolic health, HDL-based therapeutics are being developed to enhance HDL functions rather than to increase HDL-C levels. Among these, recombinant HDL and small synthetic apolipoprotein A-I mimetic peptides may hold promise for preventing and treating diabetes and cardiovascular disease.

Discovering hidden patterns: Association rules for cardiovascular diseases in type 2 diabetes mellitus

BACKGROUND

It is increasingly common to find patients affected by a combination of type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD), and studies are able to correlate their relationships with available biological and clinical evidence. The aim of the current study was to apply association rule mining (ARM) to discover whether there are consistent patterns of clinical features relevant to these diseases. ARM leverages clinical and laboratory data to the meaningful patterns for diabetic CAD by harnessing the power help of data-driven algorithms to optimise the decision-making in patient care.

AIM

To reinforce the evidence of the T2DM-CAD interplay and demonstrate the ability of ARM to provide new insights into multivariate pattern discovery.

METHODS

This cross-sectional study was conducted at the Department of Biochemistry in a specialized tertiary care centre in Delhi, involving a total of 300 consented subjects categorized into three groups: CAD with diabetes, CAD without diabetes, and healthy controls, with 100 subjects in each group. The participants were enrolled from the Cardiology IPD & OPD for the sample collection. The study employed ARM technique to extract the meaningful patterns and relationships from the clinical data with its original value.

RESULTS

The clinical dataset comprised 35 attributes from enrolled subjects. The analysis produced rules with a maximum branching factor of 4 and a rule length of 5, necessitating a 1% probability increase for enhancement. Prominent patterns emerged, highlighting strong links between health indicators and diabetes likelihood, particularly elevated HbA1C and random blood sugar levels. The ARM technique identified individuals with a random blood sugar level > 175 and HbA1C > 6.6 are likely in the "CAD-with-diabetes" group, offering valuable insights into health indicators and influencing factors on disease outcomes.

CONCLUSION

The application of this method holds promise for healthcare practitioners to offer valuable insights for enhancing patient treatment targeting specific subtypes of CAD with diabetes. Implying artificial intelligence techniques with medical data, we have shown the potential for personalized healthcare and the development of user-friendly applications aimed at improving cardiovascular health outcomes for this high-risk population to optimise the decision-making in patient care.

Insights into the Role of Glutathione Peroxidase 3 in Non-Neoplastic Diseases

Reactive oxygen species (ROSs) are byproducts of normal cellular metabolism and play pivotal roles in various physiological processes. Disruptions in the balance between ROS levels and the body's antioxidant defenses can lead to the development of numerous diseases. Glutathione peroxidase 3 (GPX3), a key component of the body's antioxidant system, is an oxidoreductase enzyme. GPX3 mitigates oxidative damage by catalyzing the conversion of hydrogen peroxide into water. Beyond its antioxidant function, GPX3 is vital in regulating metabolism, modulating cell growth, inducing apoptosis and facilitating signal transduction. It also serves as a significant tumor suppressor in various cancers. Recent studies have revealed aberrant expression of GPX3 in several non-neoplastic diseases, associating it with multiple pathological processes. This review synthesizes the current understanding of GPX3 expression and regulation, highlighting its extensive roles in noncancerous diseases. Additionally, this paper evaluates the potential of GPX3 as a diagnostic biomarker and explores emerging therapeutic strategies targeting this enzyme, offering potential avenues for future clinical treatment of non-neoplastic conditions.

Cardiovascular health metrics and diabetic nephropathy: a nationally representative cross-sectional study

BACKGROUND

The pathogenesis of diabetic nephropathy is well-documented to be multifactorial. However, research available on the association between cardiovascular health and diabetic nephropathy is limited. Thus, this study aimed to investigate these potential associations and provide guidance for disease prevention.

METHODS

We applied Life's Essential 8 (LE8) identified by the American Heart Association, which integrates multiple health behaviors and health factors to measure cardiovascular health. This study covered 4207 adults with diabetes from the National Health and Nutrition Examination Survey spanning 2007-2018. Weighted regression models assessed the estimated effect of LE8 score on the prevalence of diabetic nephropathy as well as their corresponding clinical indicators. Weighted restricted cubic spline models discussed the possible nonlinear dose-response relationships further. Subgroup analyses clarified the effects of other covariates on correlations.

RESULTS

After adjusting for all covariates, participants with moderate or high cardiovascular health showed a decreased prevalence of diabetic nephropathy (odds ratio [OR]:0.52; 95% confidence interval [CI]:0.42-0.63), and also a decrease in the urinary albumin-to-creatinine ratio [UACR] (β: - 0.83; 95% CI:- 1.00 to - 0.65). The prevalence of diabetic nephropathy and the level of UACR tended to decrease linearly as the total LE8 score increased (P for nonlinear > 0.05). Subgroup analyses showed that the effects of increased overall LE8 score and the specific cardiovascular health construct varied across age and obesity strata.

CONCLUSION

Elevated overall LE8 score was significantly associated with a lower prevalence of diabetic nephropathy in U.S. adults, and the effects of the specific cardiovascular health construct on diabetic nephropathy and their corresponding clinical indicators varied. In all, maintaining good cardiovascular health by refining LE8 metrics may help reduce the adverse effects.

Pulmonary Hypertension and Hyperglycemia-Not a Sweet Combination

Hyperglycemia and pulmonary hypertension (PH) share common pathological pathways that lead to vascular dysfunction and resultant cardiovascular complications. These shared pathologic pathways involve endothelial dysfunction, inflammation, oxidative stress, and hormonal imbalances. Individuals with hyperglycemia or pulmonary hypertension also possess shared clinical factors that contribute to increased morbidity from both diseases. This review aims to explore the relationship between PH and hyperglycemia, highlighting the mechanisms underlying their association and discussing the clinical implications. Understanding these common pathologic and clinical factors will enable early detection for those at-risk for complications from both diseases, paving the way for improved research and targeted therapeutics.

Ion channel Piezo1 activation aggravates the endothelial dysfunction under a high glucose environment

BACKGROUND

Vasculopathy is the most common complication of diabetes. Endothelial cells located in the innermost layer of blood vessels are constantly affected by blood flow or vascular components; thus, their mechanosensitivity plays an important role in mediating vascular regulation. Endothelial damage, one of the main causes of hyperglycemic vascular complications, has been extensively studied. However, the role of mechanosensitive signaling in hyperglycemic endothelial damage remains unclear.

METHODS

Vascular endothelial-specific Piezo1 knockout mice were generated to investigate the effects of Piezo1 on Streptozotocin-induced hyperglycemia and vascular endothelial injury. In vitro activation or knockdown of Piezo1 was performed to evaluate the effects on the proliferation, migration, and tubular function of human umbilical vein endothelial cells in high glucose. Reactive oxygen species production, mitochondrial membrane potential alternations, and oxidative stress-related products were used to assess the extent of oxidative stress damage caused by Piezo1 activation.

RESULTS

Our study found that in VECreERT2;Piezo1flox/flox mice with Piezo1 conditional knockout in vascular endothelial cells, Piezo1 deficiency alleviated streptozotocin-induced hyperglycemia with reduced apoptosis and abscission of thoracic aortic endothelial cells, and decreased the inflammatory response of aortic tissue caused by high glucose. Moreover, the knockout of Piezo1 showed a thinner thoracic aortic wall, reduced tunica media damage, and increased endothelial nitric oxide synthase expression in transgenic mice, indicating the relief of endothelial damage caused by hyperglycemia. We also showed that Piezo1 activation aggravated oxidative stress injury and resulted in severe dysfunction through the Ca2+-induced CaMKII-Nrf2 axis in human umbilical vein endothelial cells. In Piezo1 conditional knockout mice, Piezo1 deficiency partially restored superoxide dismutase activity and reduced malondialdehyde content in the thoracic aorta. Mechanistically, Piezo1 deficiency decreased CaMKII phosphorylation and restored the expression of Nrf2 and its downstream molecules HO-1 and NQO1.

CONCLUSION

In summary, our study revealed that Piezo1 is involved in high glucose-induced oxidative stress injury and aggravated endothelial dysfunction, which have great significance for alleviating endothelial damage caused by hyperglycemia.

Mendelian randomization analyses reveal causal relationship between liver volume and stroke

BACKGROUND

Observational studies have suggested a potential association between abdominal viscera volume and increased risk of stroke. However, the causal relationship remains unclear. This study aims to utilize Mendelian randomization (MR) to explore the genetic causal relationship between them.

METHODS

We conducted MR analysis to study the causal effects of five abdominal viscera volumes on stroke. The genetic variations of abdominal viscera volume were obtained from the UK Biobank, and the summary data for stroke and ischemic stroke were acquired from the MEGASTROKE consortium. This study employed inverse variance weighting (IVW), MR Egger, and weighted median methods. IVW served as the primary MR analysis method, supplemented by other sensitivity analyses to validate the robustness of the results.

RESULTS

We found that liver volume can causally increase the risk of stroke [odds ratio (OR): 1.13, 95 % confidence interval (CI): 1.03-1.25, P = 0.013] and ischemic stroke (OR: 1.14, 95 % CI: 1.03-1.26, P = 0.012). No causal relationships between other abdominal viscera volumes and stroke and ischemic stroke appeared to be present (P > 0.05). Sensitivity analyses confirmed the robustness of the results.

CONCLUSION

Our research findings indicate a causal relationship between liver volume and stroke, highlighting the potential role of liver volume in the onset of stroke. However, further basic and clinical research is needed to delve into the specific mechanisms underlying the relationship between liver volume and stroke, and to implement interventions aimed at reducing the impact of liver volume on stroke risk.

Quantitative Assessment of Intracellular Effectors and Cellular Response in RAGE Activation

The review delves into the methods for the quantitative assessment of intracellular effectors and cellular response of Receptor for Advanced Glycation End products (RAGE), a vital transmembrane receptor involved in a range of physiological and pathological processes. RAGE bind to Advanced Glycation End products (AGEs) and other ligands, which in turn activate diverse downstream signaling pathways that impact cellular responses such as inflammation, oxidative stress, and immune reactions. The review article discusses the intracellular signaling pathways activated by RAGE followed by differential activation of RAGE signaling across various diseases. This will ultimately guide researchers in developing targeted and effective interventions for diseases associated with RAGE activation. Further, we have discussed how PCR, western blotting, and microscopic examination of various molecules involved in downstream signaling can be leveraged to monitor, diagnose, and explore diseases involving proteins with unique post-translational modifications. This review article underscores the pressing need for advancements in molecular approaches for disease detection and management involving RAGE.

Hydrogen sulfide improves endothelial barrier function by modulating the ubiquitination degradation of KLF4 through TRAF7 S-sulfhydration in diabetic aorta

Anomalous vascular endothelium significantly contributes to various cardiovascular diseases. VE-cadherin plays a vital role in governing the endothelial barrier. Krüppel-like factor 4(KLF4), as a transcription factor, which binds the VE-cadherin promoter and enhances its transcription. Tumor necrosis factor receptor-associated factor 7 (TRAF7) is an E3 ubiquitin ligase that has been shown to modulate the degradation of KLF4. H2S can covalently modify cysteine residues on proteins through S-sulfhydration, thereby influencing the structure and functionality of the target protein. However, the role of S-sulfhydration on endothelial barrier integrity remains to be comprehensively elucidated. This study aims to investigate whether protein S-sulfhydration in the endothelium regulates endothelial integrity and its underlying mechanism. In this study, we observed that protein S-sulfhydration was reduced in the endothelium during diabetes and TRAF7 was the main target. Overexpression of TRAF7-Cys327 mutant could mitigate the endothelial barrier damage by weakening TRAF7 interaction with KLF4 and reducing ubiquitination degradation of KLF4. In conclusion, our research demonstrates that H2S plays a pivotal role in regulating S-sulfhydration of TRAF7 at Cys327. This regulation effectively inhibits the ubiquitin-mediated degradation of KLF4, resulting in an upregulation of VE-cadherin levels. This molecular mechanism contributes to the prevention of endothelial barrier damage.

Toward Ultrasound Molecular Imaging of Endothelial Dysfunction in Diabetes: Targets, Strategies, and Challenges

Diabetes vasculopathy is a significant complication of diabetes mellitus (DM), and early identification and timely intervention can effectively slow the progression. Accumulating studies have shown that diabetes causes vascular complications directly or indirectly through a variety of mechanisms. Direct imaging of the endothelial molecular changes not only identifies the early stage of diabetes vasculopathy but also sheds light on the precise treatment. Targeted ultrasound contrast agent (UCA)-based ultrasound molecular imaging (UMI) can noninvasively detect the expression status of molecular biomarkers overexpressed in the vasculature, thereby being a potential strategy for the diagnosis and treatment response evaluation of DM. Amounts of efforts have been focused on identification of the molecular targets expressed in the vasculature, manufacturing strategies of the targeted UCA, and the clinical translation for the diagnosis and evaluation of therapeutic efficacy in both micro- and macrovasculopathy in DM. This review summarizes the latest research progress on endothelium-targeted UCA and discusses their promising future and challenges in diabetes vasculopathy theranostics.

New insights of DsbA-L in the pathogenesis of metabolic diseases

Metabolic diseases, such as obesity, diabetes mellitus, and non-alcoholic fatty liver disease (NAFLD), are abnormal conditions that result from disturbances of metabolism. With the improvement of living conditions, the morbidity and mortality rates of metabolic diseases are steadily rising, posing a significant threat to human health worldwide. Therefore, identifying novel effective targets for metabolic diseases is crucial. Accumulating evidence has indicated that disulfide bond A oxidoreductase-like protein (DsbA-L) delays the development of metabolic diseases. However, the underlying mechanisms of DsbA-L in metabolic diseases remain unclear. In this review, we will discuss the roles of DsbA-L in the pathogenesis of metabolic diseases, including obesity, diabetes mellitus, and NAFLD, and highlight the potential mechanisms. These findings suggest that DsbA-L might provide a novel therapeutic strategy for metabolic diseases.

Assessing the Relationship between Indexed Epicardial Adipose Tissue Thickness, Oxidative Stress in Adipocytes, and Coronary Artery Disease Complexity in Open-Heart Surgery Patients

Background and Objectives: This cross-sectional study conducted at the Timișoara Institute of Cardiovascular Diseases, Romania, and the Centre for Translational Research and Systems Medicine from "Victor Babeș" University of Medicine and Pharmacy of Timișoara, Romania, investigated the relationship between indexed epicardial adipose tissue thickness (EATTi) and oxidative stress in epicardial adipose tissue (EAT) adipocytes in the context of coronary artery disease (CAD) among open-heart surgery patients. The objective was to elucidate the contribution of EATTi as an additional marker for complexity prediction in patients with CAD, potentially influencing clinical decision-making in surgical settings. Materials and Methods: The study included 25 patients undergoing cardiac surgery, with a mean age of 65.16 years and a body mass index of 27.61 kg/m2. Oxidative stress in EAT was assessed using the ferrous iron xylenol orange oxidation spectrophotometric assay. The patients were divided into three groups: those with valvular heart disease without CAD, patients with CAD without diabetes mellitus (DM), and patients with both CAD and DM. The CAD complexity was evaluated using the SYNTAX score. Results: The EATTi showed statistically significant elevations in the patients with both CAD and DM (mean 5.27 ± 0.67 mm/m2) compared to the CAD without DM group (mean 3.78 ± 1.05 mm/m2, p = 0.024) and the valvular disease without CAD group (mean 2.67 ± 0.83 mm/m2, p = 0.001). Patients with SYNTAX scores over 32 had significantly higher EATTi (5.27 ± 0.66 mm/m2) compared to those with lower scores. An EATTi greater than 4.15 mm/m2 predicted more complex CAD (SYNTAX score >22) with 80% sensitivity and 86% specificity. The intra- and interobserver reproducibility for the EATTi measurement were excellent (intra-class correlation coefficient 0.911, inter-class correlation coefficient 0.895). Conclusions: EATTi is significantly associated with CAD complexity in patients undergoing open-heart surgery. It serves as a reliable indicator of more intricate CAD forms, as reflected by higher SYNTAX scores. These findings highlight the clinical relevance of EATTi in pre-operative assessment, suggesting its potential utility as a prognostic marker in cardiac surgical patients.

C2CD4B Evokes Oxidative Stress and Vascular Dysfunction via a PI3K/Akt/PKCα-Signaling Pathway

High glucose-induced endothelial dysfunction is an important pathological feature of diabetic vasculopathy. While genome-wide studies have identified an association between type 2 diabetes mellitus (T2DM) and increased expression of a C2 calcium-dependent domain containing 4B (C2CD4B), no study has yet explored the possible direct effect of C2CD4B on vascular function. Vascular reactivity studies were conducted using a pressure myograph, and nitric oxide and oxidative stress were assessed through difluorofluorescein diacetate and dihydroethidium, respectively. We demonstrate that high glucose upregulated both mRNA and protein expression of C2CD4B in mice mesenteric arteries in a time-dependent manner. Notably, the inhibition of C2CD4B expression by genetic knockdown efficiently prevented hyperglycemia-induced oxidative stress, endothelial dysfunction, and loss of nitric oxide (NO) bioavailability. Recombinant C2CD4B evoked endothelial dysfunction of mice mesenteric arteries, an effect associated with increased reactive oxygen species (ROS) and decreased NO production. In isolated human umbilical vein endothelial cells (HUVECs), C2CD4B increased phosphorylation of endothelial nitric oxide synthase (eNOS) at the inhibitory site Thr495 and reduced eNOS dimerization. Pharmacological inhibitors of phosphoinositide 3-kinase (PI3K), Akt, and PKCα effectively attenuated oxidative stress, NO reduction, impairment of endothelial function, and eNOS uncoupling induced by C2CD4B. These data demonstrate, for the first time, that C2CD4B exerts a direct effect on vascular endothelium via a phosphoinositide 3-kinase (PI3K)/Akt/PKCα-signaling pathway, providing a new perspective on C2CD4B as a promising therapeutic target for the prevention of oxidative stress in diabetes-induced endothelial dysfunction.

Extracellular Superoxide Dismutase Attenuates Hepatic Oxidative Stress in Nonalcoholic Fatty Liver Disease through the Adenosine Monophosphate-Activated Protein Kinase Activation

Oxidative stress is key in type 2 diabetes-associated nonalcoholic fatty liver disease (NAFLD). We explored whether extracellular superoxide dismutase (EC-SOD) activates adenosine monophosphate-activated protein kinase (AMPK) to enhance antioxidant synthesis and lipid metabolism in NAFLD. Human recombinant EC-SOD (hEC-SOD) was administered to 8-week-old male C57BLKS/J db/db mice through intraperitoneal injection once a week for 8 weeks. Target molecules involved in oxidative stress and lipid metabolism were investigated. hEC-SOD improved insulin resistance and systemic and hepatic oxidative stress characterized by increases in urinary 8-hydroxy-deoxyguanosine and 8-isoprostane levels in db/db mice and a decrease in DHE expression in the liver, respectively. Hepatic SOD3 expression in db/db mice was reversed by hEC-SOD, which improved hepatic steatosis, inflammation with M2 polarization, apoptosis, autophagy, fibrosis and lipid metabolism in db/db mice, as reflected by the changes in serum and hepatic markers, monocyte chemoattractant protein-1, tumor necrosis factor-α, TUNEL-positive cells, Bcl-2/BAX ratio, beclin1 and LC3-II/LC3-1. At the molecular level, hEC-SOD increased phosphorylated-AMPK related to CaMKKß, activation of peroxisome proliferative-activated receptor-gamma coactivator (PGC)-1α and dephosphorylation of forkhead box O (FoxO)1 and their subsequent downstream signaling. In HepG2Cs cells using AMPKα1 and AMPKα2 siRNA, hEC-SOD demonstrated a protective effect via the direct activation of both AMPK-PGC-1α and AMPK-FoxO1. EC-SOD might be a potential therapeutic agent for NAFLD through the activation of AMPK-PGC-1α and AMPK-FoxO1 signaling in hepatocytes, which modulates lipid metabolism, leading to anti-inflammatory, antioxidative and antiapoptotic effects and improving autophagy in the liver.