Antidiabetic agents: Potential anti-inflammatory activity beyond glucose control

Association of Novel Antihyperglycemic Drugs Versus Metformin With a Decrease in Asthma Exacerbations

BACKGROUND

Similar to metformin, dipeptidyl peptidase-4 inhibitors (DPP-4 Is), glucagon-like peptidase 1 receptor agonists (GLP-1 RAs), and sodium glucose co-transporter-2 inhibitors (SGLT-2 Is) may improve control of asthma owing to their multiple potential mechanisms, including differential improvements in glycemic control, direct anti-inflammatory effects, and systemic changes in metabolism.

OBJECTIVE

To investigate whether these novel antihyperglycemic drugs were associated with fewer asthma exacerbations compared with metformin in patients with asthma comorbid with type 2 diabetes.

METHODS

Using a Japanese national administrative database, we constructed 3 active comparators-new user cohorts of 137,173 patients with a history of asthma starting the novel antihyperglycemic drugs and metformin between 2014 and 2022. Patient characteristics were balanced using overlap propensity score weighting. The primary outcome was the first exacerbation requiring systemic corticosteroids, and the secondary outcomes included the number of exacerbations requiring systemic corticosteroids.

RESULTS

DPP-4 Is and GLP-1 RAs were associated with a higher incidence of exacerbations requiring systemic corticosteroids compared with metformin (DPP-4 Is: 18.2 vs 17.4 per 100 person-years, hazard ratio: 1.09, 95% confidence interval [CI]: 1.05-1.14; GLP-1 RAs: 24.9 vs 19.0 per 100 person-years, hazard ratio: 1.14, 95% CI: 1.01-1.28). In contrast, the incidence of exacerbations requiring systemic corticosteroids was similar between the SGLT-2 Is and metformin groups (17.3 vs 18.1 per 100 person-years, hazard ratio: 1.00, 95% CI: 0.97-1.03). While DPP-4 Is and GLP-1 RAs were associated with more exacerbations requiring systemic corticosteroids, SGLT-2 Is were associated with slightly fewer exacerbations requiring systemic corticosteroids (53.7 vs 56.6 per 100 person-years, rate ratio: 0.95, 95% CI: 0.91-0.99).

CONCLUSIONS

While DPP-4 Is and GLP-1 RAs were associated with poorer control of asthma compared with metformin, SGLT-2 Is offered asthma control comparable to that of metformin.

Possible role of metformin as an antidepressant in diabetes

OBJECTIVE

Metformin (MET) is a drug used in the treatment of type 2 diabetes due to its insulin receptor sensitizing properties and anti-hepatic gluconeogenesis effect. One of the comorbidities in diabetes is the depression. This review aimed at summarizing the results of the available MET, depression and diabetes studies to clarify the possible role of MET in the depression during diabetes.

METHODS

A bibliographic search on PubMed, Embase, PsycINFO, Web of Science, Cochrane Central for studies referring to MET, depression and diabetes.

RESULTS

Several studies have associated depression to the chronic inflammation that characterizes diabetes. Additionally MET is an anti-inflammatory molecule that generally acts by activating AMPK and inhibiting the NF-kB factor. In the context of diabetes, MET can act directly as an anti-inflammatory drug as well as inhibiting other pro-inflammatory molecules. In this regard, MET may inhibit the pro-inflammatory effects of angiotensin II. By facilitating the action of insulin and reducing hepatic gluconeogenesis, MET reduces circulating glucose levels, decreasing the formation of advanced glycation end products and therefore inflammation. During diabetes, the gut microbiota and the permeability of the intestinal barrier are altered, causing high levels of circulating lipopolysaccharides (LPS), which induce inflammation. MET can normalize the microbiota and the intestinal barrier permeability reducing the levels of LPS and inflammation. Clinical and experimental studies show the anti-depressant effect of MET mediated by different mechanisms both at the peripheral level and in the central nervous system.

CONCLUSION

Therefore, MET as an anti-inflammatory drug can decrease symptoms of depression and represents a therapeutic approach to improve the psychological state of patients with diabetes. Additionally, insulin also has an anti-inflammatory effect that could act together with MET.

Association Between Antidiabetic Drugs and Delirium: A Study Based on the Adverse Drug Event Reporting Database in Japan

BACKGROUND AND OBJECTIVE

Several associations between diabetes mellitus and delirium have been reported; however, they have been inconsistent, and evidence on the effects of antidiabetic medications on delirium is also limited. This study aimed to investigate whether the use of antidiabetic drugs is a risk factor for delirium development.

METHODS

Using the Japanese Adverse Event Reporting Database, we analyzed 662,899 reports between 2004 and 2022. Reporting odds ratios (RORs) and 95% confidence intervals (CIs) for delirium associated with diabetes and using each antidiabetic medication were calculated after adjusting for potential confounders.

RESULTS

Overall, 8892 of the reports analyzed were associated with delirium. A comparison of the incidence of delirium between patients with and without diabetes showed no significant difference, with 1.34% in patients without diabetes and 1.37% in those with diabetes. In each antidiabetic medication, signals for delirium were detected for sulfonylurea (crude ROR, 1.35; 95% CI 1.21-1.51) and insulin (crude ROR, 1.28; 95% CI 1.13-1.44). These results were maintained even after adjusting for factors with potential confounders (sulfonylurea: adjusted ROR, 1.75; 95% CI 1.54-2.00, insulin: adjusted ROR, 1.35; 95% CI 1.20-1.54).

CONCLUSIONS

Our results suggest no association between diabetes and delirium; however, using sulfonylurea and insulin may be associated with delirium development. Nonetheless, these findings should be validated in future studies.

Steatotic liver disease, MASLD and risk of chronic kidney disease

With the rising tide of fatty liver disease related to metabolic dysfunction worldwide, the association of this common liver disease with chronic kidney disease (CKD) has become increasingly evident. In 2020, the more inclusive term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace the old term non-alcoholic fatty liver disease (NAFLD). In 2023, a modified Delphi process was led by three large pan-national liver associations. There was consensus to change the fatty liver disease nomenclature and definition to include the presence of at least one of five common cardiometabolic risk factors as diagnostic criteria. The name chosen to replace NAFLD was metabolic dysfunction-associated steatotic liver disease (MASLD). The change of nomenclature from NAFLD to MAFLD and then MASLD has resulted in a reappraisal of the epidemiological trends and associations with the risk of developing CKD. The observed association between MAFLD/MASLD and CKD and our understanding that CKD can be an epiphenomenon linked to underlying metabolic dysfunction support the notion that individuals with MASLD are at substantially higher risk of incident CKD than those without MASLD. This narrative review provides an overview of the literature on (a) the evolution of criteria for diagnosing this highly prevalent metabolic liver disease, (b) the epidemiological evidence linking MASLD to the risk of CKD, (c) the underlying mechanisms by which MASLD (and factors strongly linked with MASLD) may increase the risk of developing CKD, and (d) the potential drug treatments that may benefit both MASLD and CKD.

Targeting immunometabolic pathways for combination therapy in Alzheimer's disease

The recent success of disease-modifying anti-amyloid monoclonal antibodies in slowing Alzheimer's disease (AD) symptoms has been an exciting step forward for the field. Despite successfully clearing amyloid from the brain, however, only modest symptomatic improvement has been demonstrated, and treatment-related side effects such as amyloid-related imaging abnormalities (ARIA) limit use for some. These limitations suggest that fully efficacious AD treatment may require combination therapy regimens, as are used in other complex disorders such as cancer and HIV. One reasonable strategy may be to use agents that address the biological changes that predict future amyloid accumulation, or accompany amyloid accumulation in preclinical disease states. Immunometabolic pathways, including the insulin signaling pathway, are dysregulated at the earliest stages of AD, concomitant with amyloid accumulation. It is plausible that agents that target these pathways may work synergistically with anti-amyloid therapies to halt AD progression. Insulin signaling is integrally involved in innate and adaptive immune systems, with pleiotropic effects that moderate pro- and anti-inflammatory responses. Metabolic modulators that enhance insulin sensitivity and function, such as GLP-1 receptor agonists, SGLT2 inhibitors, and insulin itself have been shown to improve immune function and reduce chronic inflammation. Additional effects of insulin and metabolic modulators demonstrated in preclinical and clinical studies of AD include increased clearance of amyloid-β, slowed tau progression, improved vascular function and lipid metabolism, reduced synaptotoxicity, and improved cognitive and functional outcomes. A large number of compounds that treat metabolic disorders have been extensively characterized with respect to mechanism of action and safety, and thus are readily available to be repurposed for combination therapy protocols. Determining the most successful combination regimens of these agents together with disease-modifying therapies, and the appropriate timing of treatment, are promising next steps in the quest to treat and prevent AD.

Metformin derivatives - Researchers' friends or foes?

Metformin has been used for ages to treat diabetes mellitus due to its safety profile and low cost. However, metformin has variable pharmacokinetics in patients, and due to its poor oral absorption, the therapeutic doses are relatively high, causing unpleasant gastrointestinal adverse effects. Therefore, novel derivatives of metformin have been synthesized during the past decades. Particularly, after the mid-2000 s, when organic cation transporters were identified as the main metformin carriers, metformin derivatives have been under intensive investigation. Nevertheless, due to the biguanide structure, derivatives of metformin have been challenging to synthesize. Moreover, the mechanisms of metformin's action are not fully understood to date, and since it has multifunctional properties, the interests have switched to re-purposing for other diseases. Indeed, metformin derivatives have been demonstrated in many cases to be more effective than metformin itself and have the potential to be used in different diseases, including several types of cancers and neurodegenerative diseases. On the other hand, the pleiotropic nature of metformin and its derivatives can also create challenges. Not all properties are fit for all diseases. In this review, the history of the development of metformin-like compounds is summarized, and insights into their potential for future drug discovery are discussed.

Metformin and Aspirin: Anticancer effects on A549 and PC3 cancer cells and the mechanisms of action

Metformin exerts its anticancer effect through two mechanisms, directly affecting the tumor and indirectly reducing systemic insulin levels. The anticancer effects of aspirin occur by inhibiting Cyclooxygenase (COX)-2. COX-2 is absent in many cell types under normal conditions and increases under pathological conditions such as cancer. This study aims to investigate the effect of metformin and aspirin and their combination of them on A549 and PC3 cell lines. Metformin and aspirin were investigated separately and in combination on two cancer cell lines, A549 and PC3. The examined groups include the negative control of untreated cells and the positive control of cisplatin and drugs at concentrations of 15, 10, and 20 μg/ mL to investigate the mechanism of oxidative stress factors (reactive oxygen species, lipid peroxidation, Glutathione (GSH)) and apoptosis (lactate dehydrogenase). The results showed that aspirin, metformin, and their combination could affect cancer cell growth by damaging mitochondria, releasing reactive oxygen species, and activating the oxidative stress pathway. Also, these two drugs show the activation of the apoptotic pathway in cancer cells by increasing the lactate dehydrogenase factor and releasing it from the cells. By disrupting the balance of oxidants and antioxidants in the cell, metformin and aspirin cause an increase in the level of reactive oxygen species and a decrease in the level of glutathione reserves, followed by an increase in the level of lipid peroxidation and a decrease in cell viability. Unlike common chemotherapy drugs, these drugs have no known severe side effects; Therefore, in the not-so-distant future, these drugs can also be used as anticancer drugs.

Highlights

Metformin and aspirin, commonly used drugs for diabetes and inflammation, inhibit the growth of cancer cell lines, A549 and PC3.Metformin and aspirin, either separately or in combination, can potentially impede cancer cell growth by disrupting mitochondrial function, inducing the release of reactive oxygen species (ROS), and activating oxidative stress pathways.Furthermore, these drugs can trigger apoptosis, a programmed cell death mechanism, in cancer cells by increasing lactate dehydrogenase (LDH) levels and facilitating its release from the cells.

Acute uveitis caused by abnormal glucose and lipid metabolism: a case report

PURPOSE

This report describes a rare case of acute uveitis with severe anterior chamber inflammation due to abnormal glucose and lipid metabolism.

CASE PRESENTATION

A 31-year-old male patient complained of redness in the right eye with decreased visual acuity for 3 days. Ocular examination revealed a milky white clouding of the right anterior chamber of the eye. Two clusters of yellowish-white exudates were visible on the surface of the iris in the upper nasal and temporal areas in addition to elevated intraocular pressure. He had a previous diagnosis of type 2 diabetes mellitus (T2DM). Laboratory tests suggested hyperlipidemia and ketoacidosis. After admission, topical glucocorticoids, mydriasis, and intraocular pressure-lowering drugs combined with hypoglycemic and lipid-lowering therapy and fluid replacement therapy were given immediately. After 10 days of treatment, the uveitis and systemic condition of the right eye were effectively controlled and improved.

CONCLUSION

Abnormal glucose and lipid metabolism leads to impairment of the blood-aqueous barrier, which causes a severe uveitis response in the anterior chamber. After the use of topical steroids and mydriatic eye drops combined with systemic hypoglycemic and lipid-lowering interventions, the condition was significantly relieved.

Novel Drugs for the Management of Diabetes Kidney Transplant Patients: A Literature Review

The management of diabetes and renal failure is changing thanks to the appearance of new drugs such as glucagon-like peptide 1 receptor agonists (GLP1-RA) and sodium-glucose cotransporter type 2 inhibitors (SGLT2i) that have benefits in terms of survival and cardiorenal protection. Based on the potential mechanisms of GLP1-RA, kidney transplant recipients (KTRs) could benefit from their effects. However, high-quality studies are needed to demonstrate these benefits, in the transplant population, especially those related to cardiovascular benefits and renal protection. Studies with SGLT2i performed in KTRs are much less potent than in the general population and therefore no benefits in terms of patient or graft survival have been clearly demonstrated in this population to date. Additionally, the most frequently observed side effects could be potentially harmful to this population profile, including severe or recurrent urinary tract infections and impaired kidney function. However, benefits demonstrated in KTRs are in line with a known potential effects in cardiovascular and renal protection, which may be essential for the outcome of transplant recipients. Better studies are still needed to confirm the benefits of these new oral antidiabetics in the renal transplant population. Understanding the characteristics of these drugs may be critical for KTRs to be able to benefit from their effects without being damaged. This review discusses the results of the most important published studies on KTRs with GLP1-RA and SGLT2i as well as the potential beneficial effects of these drugs. Based on these results, approximate suggestions for the management of diabetes in KTRs were developed.

Antidiabetic Drugs Can Reduce the Harmful Impact of Chronic Smoking on Post-Traumatic Brain Injuries

Traumatic Brain Injury (TBI) is a primary cause of cerebrovascular and neurological disorders worldwide. The current scientific researchers believe that premorbid conditions such as tobacco smoking (TS) can exacerbate post-TBI brain injury and negatively affect recovery. This is related to vascular endothelial dysfunction resulting from the exposure to TS-released reactive oxygen species (ROS), nicotine, and oxidative stress (OS) stimuli impacting the blood-brain barrier (BBB) endothelium. Interestingly, these pathogenic modulators of BBB impairment are similar to those associated with hyperglycemia. Antidiabetic drugs such as metformin (MF) and rosiglitazone (RSG) were shown to prevent/reduce BBB damage promoted by chronic TS exposure. Thus, using in vivo approaches, we evaluated the effectiveness of post-TBI treatment with MF or RSG to reduce the TS-enhancement of BBB damage and brain injury after TBI. For this purpose, we employed an in vivo weight-drop TBI model using male C57BL/6J mice chronically exposed to TS with and without post-traumatic treatment with MF or RSG. Our results revealed that these antidiabetic drugs counteracted TS-promoted downregulation of nuclear factor erythroid 2-related factor 2 (NRF2) expression and concomitantly dampened TS-enhanced OS, inflammation, and loss of BBB integrity following TBI. In conclusion, our findings suggest that MF and RSG could reduce the harmful impact of chronic smoking on post-traumatic brain injuries.

In silico prediction of the possible antidiabetic and anti-inflammatory targets of Nymphaea lotus-derived phytochemicals and mechanistic insights by molecular dynamics simulations

Nymphaea lotus is used traditionally for the treatment of diabetes and its complications. However, the mode of action and the likely bioactive phytochemicals involved are not yet fully explored. GC-MS analysis was employed to identify the inherent compounds in N. lotus leaves. To gain an insight into the antidiabetic mode of action of this plant, the identified phytochemicals were subjected to computational studies against four molecular targets of diabetes, dipeptidyl peptidase-4, glycogen synthase kinase 3, NADPH oxidase (NOX), sodium-glucose co-transporter-2, and one target of inflammation, cyclooxygenase-2. Compounds with notable binding affinity were subjected to druggability test. Results from molecular docking showed that seven of the compounds investigated exhibited druggability properties and had outstanding binding affinity values for these targets relative to values obtained for the respective standards of each of the targets. Analysis of the MD trajectories from a 100 ns atomistic run shows that the integrities of the complex systems were more stable and preserved throughout the simulation than the unbound protein. These results indicated that the antidiabetic and anti-inflammatory effects of these compounds might be via the inhibition of these targets, laying the foundation for further studies, such as in vitro and in vivo studies to fully validate the anti-diabetic agents from this plant.Communicated by Ramaswamy H. Sarma.

Association of Sodium-Glucose Cotransporter-2 Inhibitors With Incident Atrial Fibrillation in Older Adults With Type 2 Diabetes

IMPORTANCE

Sodium-glucose cotransporter-2 inhibitors (SGLT-2is) have demonstrated many cardiovascular and kidney function benefits for patients with type 2 diabetes (T2D). However, the results of SGLT-2i use in primary prevention of atrial fibrillation (AF) were inconsistent in clinical trials, and incident AF was not a prespecified end point.

OBJECTIVE

To examine incident AF with initiation of an SGLT-2i compared with initiation of a dipeptidyl peptidase-4 inhibitor (DPP-4i) or a glucagonlike peptide-1 receptor agonist (GLP-1RA) among older adults (aged ≥66 years) with T2D in routine clinical practice.

DESIGN, SETTING, AND PARTICIPANTS

A population-based new-user cohort study included older adults with T2D who had no history of AF and were enrolled in Medicare fee-for-service from April 1, 2013, to December 31, 2018. Data analysis was performed from June 28 to December 1, 2021.

EXPOSURES

To control for potential confounding, new users of SGLT-2i were 1:1 propensity score (PS)-matched to new users of DPP-4is or GLP-1RAs in 2 pairwise comparisons based on 138 baseline covariates.

MAIN OUTCOMES AND MEASURES

The primary outcome was incident AF, defined as an inpatient diagnosis code for AF. Hazard ratios (HRs) and rate differences (RDs) per 1000 person-years, with their 95% CIs, were estimated in the PS-matched groups.

RESULTS

New users of SGLT-2is were 1:1 PS-matched to new users of a DPP-4i (n = 74 868) or GLP-1RA (n = 80 475). Overall, the mean (SD) age of study participants was 72 (5) years, and 165 984 were women (53.4%). The risk of incident AF was lower in the SGLT-2i group than the matched DPP-4i group (HR, 0.82; 95% CI, 0.76 to 0.89; RD, -3.7; 95% CI, -5.2 to -2.2 per 1000 person-years) or the matched GLP-1RA group (HR, 0.90; 95% CI, 0.83 to 0.98; RD, -1.8; 95% CI, -3.2 to -0.3 per 1000 person-years). Results were consistent across several sensitivity and subgroup analyses.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that the initiation of an SGLT-2i was associated with a reduced risk of incident AF compared with a DPP-4i or GLP-1RA. The results may be helpful when weighing the potential risks and benefits of various glucose level-lowering agents in older adults with T2D.

Autophagy-nutrient sensing pathways in diabetic complications

The incidence of diabetes has been increasing in recent decades which is affecting the population of both, developed and developing countries. Diabetes is associated with micro and macrovascular complications which predominantly result from hyperglycemia and disrupted metabolic pathways. Persistent hyperglycemia leads to increased reactive oxygen species (ROS) generation, formation of misfolded and abnormal proteins, and disruption of normal cellular functioning. The inability to maintain metabolic homeostasis under excessive energy and nutrient input, which induces insulin resistance, is a crucial feature during the transition from obesity to diabetes. According to various study reports, redox alterations, intracellular stress and chronic inflammation responses have all been linked to dysregulated energy metabolism and insulin resistance. Autophagy has been considered a cleansing mechanism to prevent these anomalies and restore cellular homeostasis. However, disrupted autophagy has been linked to the pathogenesis of metabolic disorders such as obesity and diabetes. Recent studies have reported that the regulation of autophagy has a beneficial role against these conditions. When there is plenty of food, nutrient-sensing pathways activate anabolism and storage, but the shortage of food activates homeostatic mechanisms like autophagy, which mobilises internal stockpiles. These nutrient-sensing pathways are well conserved in eukaryotes and are involved in the regulation of autophagy which includes SIRT1, mTOR and AMPK. The current review focuses on the role of SIRT1, mTOR and AMPK in regulating autophagy and suggests autophagy along with these nutrient-sensing pathways as potential therapeutic targets in reducing the progression of various diabetic complications.

Metformin alleviates prolonged isoflurane inhalation induced cognitive decline via reducing neuroinflammation in adult mice

With the widespread use of volatile anesthetic agents in the prolonged sedation for COVID-19 pneumonia and ARDS, there is an urgent need to investigate the effects and treatments of lengthy low-concentration inhaled anesthetics exposure on cognitive function in adults. Previous studies showed that general anesthetics dose- and exposure length-dependently induced neuroinflammatory response and cognitive decline in neonatal and aging animals. The anti-diabetes drug metformin has anti-neuroinflammation effects by modulating microglial polarization and inhibiting astrocyte activation. In this study, we demonstrated that the inhalation of 1.3% isoflurane (a sub-minimal alveolar concentration, sub-MAC) for 6 h impaired recognition of novel objects from Day 1 to Day3 in adult mice. Prolonged sub-MAC isoflurane exposure also triggered typically reactive microglia and A1-like astrocytes in the hippocampus of adult mice on Day 3 after anesthesia. In addition, prolonged isoflurane inhalation switched microglia into a proinflammatory M1 phenotype characterized by elevated CD68 and iNOS as well as decreased arginase-1 and IL-10. Metformin pretreatment before anesthesia enhanced cognitive performance in the novel object test. The positive cellular modifications promoted by metformin pretreatment included the inhibition of reactive microglia and A1-like astrocytes and the polarization of microglia into M2 phenotype in the hippocampus of adult mice. In conclusion, prolonged sub-MAC isoflurane exposure triggered significant hippocampal neuroinflammation and cognitive decline in adult mice which can be alleviated by metformin pretreatment via inhibiting reactive microglia and A1-like astrocytes and promoting microglia polarization toward anti-inflammatory phenotype in the hippocampus.

Comparing the effects of twice-daily exenatide and insulin on renal function in patients with type 2 diabetes mellitus: secondary analysis of a randomized controlled trial

This is a secondary analysis of a randomized controlled trial (RCT) on the effects of the glucagon-like peptide-1 receptor agonists exenatide and insulin aspartate 30 injection on carotid intima-media thickness. Here, we report the renal outcomes of the intervention in patients with type 2 diabetes mellitus (T2DM). Data from the RCT study was used to evaluate the effect of exenatide or insulin given for 52 weeks on estimated glomerular filtration rate (eGFR) in patients with T2DM. The primary end point was the change in the eGFR from baseline between the exenatide and insulin groups in normal versus overweight patients and patients with obesity. The secondary end point was the correlation between change in eGFR and oxidative stress, glycemic control, and dyslipidemia. There was a significant difference in eGFR between the insulin and exenatide groups at 52 weeks (p=0.0135). Within the insulin group, the eGFR remained below baseline at 52 weeks in all patients, and there was an increase in body weight in the normal group compared with the overweight patients and patients with obesity. The opposite was observed in the exenatide group. A decrease in body weight was prominent in the exenatide group at 52 weeks (p<0.05), the eGFR was below baseline in overweight patients and patients with obesity and significantly above baseline in the normal group (p<0.05). The eGFR was positively correlated to 8-oxo-7,8-dihydroguanosine in the insulin group (p<0.05) but not the exenatide group. It can be concluded that compared with insulin, exenatide may improve renal function in overweight patients and patients with obesity more than in normal-weight patients with T2DM, but a further RCT is needed to confirm this effect.

Mitochondrial Dysfunction and Oxidative Stress in Rheumatoid Arthritis

Control of excessive mitochondrial oxidative stress could provide new targets for both preventive and therapeutic interventions in the treatment of chronic inflammation or any pathology that develops under an inflammatory scenario, such as rheumatoid arthritis (RA). Increasing evidence has demonstrated the role of mitochondrial alterations in autoimmune diseases mainly due to the interplay between metabolism and innate immunity, but also in the modulation of inflammatory response of resident cells, such as synoviocytes. Thus, mitochondrial dysfunction derived from several danger signals could activate tricarboxylic acid (TCA) disruption, thereby favoring a vicious cycle of oxidative/mitochondrial stress. Mitochondrial dysfunction can act through modulating innate immunity via redox-sensitive inflammatory pathways or direct activation of the inflammasome. Besides, mitochondria also have a central role in regulating cell death, which is deeply altered in RA. Additionally, multiple evidence suggests that pathological processes in RA can be shaped by epigenetic mechanisms and that in turn, mitochondria are involved in epigenetic regulation. Finally, we will discuss about the involvement of some dietary components in the onset and progression of RA.

Quercetin Impedes Th17 Cell Differentiation to Mitigate Arthritis Involving PPARγ-Driven Transactivation of SOCS3 and Redistribution Corepressor SMRT from PPARγ to STAT3

SCOPE

Quercetin (QU) is one of the most abundant flavonoids in plants and has attracted the attention of researchers because of its remarkable antirheumatoid arthritis (RA) effects and extremely low adverse reactions. However, the underlying mechanism needs further study.

METHODS AND RESULTS

Flow cytometry, immunofluorescence, enzyme linked immunosorbent assay （ELISA）, and quantitative real-time polymerase chain reaction （qRT-PCR） reveal the obvious inhibitory effects of QU on Th17 cell differentiation in arthritic mice. More importantly, QU markedly limits the development of Th17 cell polarization, which is virtually compromised by the treatment with peroxisome proliferator activated receptor γ (PPARγ) inhibitor GW9662 and knockdown of PPARγ. Additionally, molecular dynamics simulation and immunofluorescence exhibit QU directly binds to PPARγ and increases PPARγ nuclear translocation. Besides, QU confers its moderation effect on suppressor of cytokine signaling protein (SOCS3)/signal transducer and activator of transcription 3 (STAT3) axis partially depending on PPARγ. Furthermore, coimmunoprecipitation shows QU redistributes the corepressor silencing mediator for retinoid and thyroid-hormone receptors (SMRT) from PPARγ to STAT3. Finally, the inhibition of Th17 response and the antiarthritic effect of QU are nullified by GW9662 treatment in arthritic mice.

CONCLUSION

QU targets PPARγ and consequently inhibits Th17 cell differentiation by dual inhibitory activity of STAT3 to exert antiarthritic effect. The findings facilitate its development and put forth a stage for uncovering the mechanism of other naturally occurring compounds with chemical structures similar to QU.

Obesity and Dyslipidemia Synergistically Exacerbate Psoriatic Skin Inflammation

Patients with psoriasis are frequently complicated with metabolic syndrome; however, it is not fully understood how obesity and dyslipidemia contribute to the pathogenesis of psoriasis. To investigate the mechanisms by which obesity and dyslipidemia exacerbate psoriasis using murine models and neonatal human epidermal keratinocytes (NHEKs), we used wild-type and Apoe-deficient dyslipidemic mice, and administered a high-fat diet for 10 weeks to induce obesity. Imiquimod was applied to the ear for 5 days to induce psoriatic dermatitis. To examine the innate immune responses of NHEKs, we cultured and stimulated NHEKs using IL-17A, TNF-α, palmitic acid, and leptin. We found that obesity and dyslipidemia synergistically aggravated psoriatic dermatitis associated with increased gene expression of pro-inflammatory cytokines and chemokines. Treatment of NHEKs with palmitic acid and leptin amplified pro-inflammatory responses in combination with TNF-α and IL-17A. Additionally, pretreatment with palmitic acid and leptin enhanced IL-17A-mediated c-Jun N-terminal kinase phosphorylation. These results revealed that obesity and dyslipidemia synergistically exacerbate psoriatic skin inflammation, and that metabolic-disorder-associated inflammatory factors, palmitic acid, and leptin augment the activation of epidermal keratinocytes. Our results emphasize that management of concomitant metabolic disorders is essential for preventing disease exacerbation in patients with psoriasis.

Identification of key candidate genes and biological pathways in the synovial tissue of patients with rheumatoid arthritis

The aim of the present study was to identify potential key candidate genes and mechanisms associated with rheumatoid arthritis (RA). Gene expression data from GSE55235, GSE55457 and GSE1919 datasets were downloaded from the Gene Expression Omnibus database. These datasets comprised 78 tissue samples collectively, including 25 healthy synovial membrane samples and 28 RA synovial membrane samples, whilst the 25 osteoarthritis (OA) samples were not included in the analysis. The differentially expressed genes (DEGs) between the two types of samples were identified with the Linear Models for Microarray Analysis package in R. Gene Ontology (GO) functional term and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analyses were also performed. In addition, Protein-Protein Interaction (PPI) network and module analyses were visualized using Cytoscape, and subsequent hub gene identification as well as GO and KEGG enrichment analyses of the modules was performed. Finally, reverse transcription-quantitative PCR (RT-qPCR) was used to validate the expression of the DEGs identified by GO and KEGG analysis in vitro. The analysis identified 491 DEGs, including 289 upregulated and 202 downregulated genes, which were mainly enriched in the following pathways: ‘Cytokine-cytokine receptor interaction’, ‘Rheumatoid arthritis’, ‘Chemokine signaling pathway’, ‘Intestinal immune network for IgA production’ and ‘Primary immunodeficiency’. The top 10 hub genes identified from the PPI network were IL-6, protein tyrosine phosphatase receptor type C, VEGFA, CD86, EGFR, C-X-C chemokine receptor type 4, matrix metalloproteinase 9, CC-chemokine receptor type (CCR)7, CCR5 and selectin L. KEGG signaling pathway enrichment analysis of the top two modules identified from the PPI network revealed that the genes in Module 1 were mainly enriched in the ‘Cytokine-cytokine receptor interaction’ and ‘Chemokine signaling pathway’, whereas analysis of Module 2 revealed that the genes were mainly enriched in ‘Primary immunodeficiency’ and ‘Cytokine-cytokine receptor interaction’. Finally, the results of the RT-qPCR and western blot analysis demonstrated that the expression levels of inflammation and NF-κB signaling pathway-related mRNAs were significantly upregulated following lipopolysaccharide stimulation. In conclusion, the findings of the present study identified key genes and signaling pathways associated with RA, which may improve the current understanding of the molecular mechanisms underlying its development and progression. The identified hub genes may also be used as potential targets for RA diagnosis and treatment.

Lower Prevalence of Osteoporosis in Patients with COPD Taking Anti-Inflammatory Compounds for the Treatment of Diabetes: Results from COSYCONET

Background

Patients with chronic obstructive pulmonary disease (COPD) often have osteoporosis and diabetes as comorbid conditions. Anti-diabetic medication, including metformin, has protective effects on osteoporosis in experimental studies. We therefore studied whether patients with COPD receiving anti-diabetic medication had a lower osteoporosis prevalence in a large COPD cohort, COSYCONET.

Methods

Assessment of osteoporosis was based on patients’ reports of physician-based diagnoses and the presence of disease-specific medication. The predictive value of physical characteristics, lung function, comorbidities, cardiovascular medication, and the use of anti-inflammatory diabetes medication, including metformin, sulfonylureas, glinides or DPP4I, was evaluated using logistic regression analysis. ClinicalTrials.gov: NCT01245933.

Results

In total, 2222 patients were eligible for analysis (863 [39%] female, mean age 65 y), 515 of whom had higher symptoms and exacerbations (Global Initiative for Chronic Obstructive Lung Disease group D). Osteoporosis was present in 15.8% of the overall cohort, and in 24.1% of GOLD D patients. Regression analyses identified the following as associated with osteoporosis (p < 0.05): female sex, higher age, lower body-mass index, asthma, higher air trapping, oral steroids, and cardiovascular medication. Although oral anti-diabetic medication was overall not associated with a lower prevalence of osteoporosis (p = 0.131), anti-inflammatory anti-diabetic medication (p = 0.009) and metformin-containing therapy (p = 0.039) were. This was driven by GOLD D patients.

Conclusion

In a large COPD cohort, anti-inflammatory diabetes therapy, including metformin, was associated with a lower prevalence of osteoporosis, especially in patients with higher symptoms and exacerbations. These findings suggest a protective effect of common anti-diabetic medication on osteoporosis, possibly as a result of attenuated systemic inflammation.

Adverse Effects of Metformin From Diabetes to COVID-19, Cancer, Neurodegenerative Diseases, and Aging: Is VDAC1 a Common Target?

Metformin has been used for treating diabetes mellitus since the late 1950s. In addition to its antihyperglycemic activity, it was shown to be a potential drug candidate for treating a range of other diseases that include various cancers, cardiovascular diseases, diabetic kidney disease, neurodegenerative diseases, renal diseases, obesity, inflammation, COVID-19 in diabetic patients, and aging. In this review, we focus on the important aspects of mitochondrial dysfunction in energy metabolism and cell death with their gatekeeper VDAC1 (voltage-dependent anion channel 1) as a possible metformin target, and summarize metformin’s effects in several diseases and gut microbiota. We question how the same drug can act on diseases with opposite characteristics, such as increasing apoptotic cell death in cancer, while inhibiting it in neurodegenerative diseases. Interestingly, metformin’s adverse effects in many diseases all show VDAC1 involvement, suggesting that it is a common factor in metformin-affecting diseases. The findings that metformin has an opposite effect on various diseases are consistent with the fact that VDAC1 controls cell life and death, supporting the idea that it is a target for metformin.

Effect of anti-diabetic drugs in dialysis patients with diabetes: a nationwide retrospective cohort study

BACKGROUND

Type 2 diabetes mellitus is common in patients undergoing dialysis. However, the association between anti-diabetic drug use and survival outcomes is rarely discussed. We aimed to investigate whether continued anti-diabetic medication use affects the survival of diabetic dialysis patients and whether different hypoglycemic drug use influences prognosis.

METHODS

Using a nationwide database, we enrolled patients with incident end-stage renal disease under maintenance dialysis during 2011-2015 into the pre-existing diabetes dialysis (PDD), incident diabetes after dialysis (IDD), and non-diabetic dialysis (NDD) groups. The PDD group was further subclassified into patients who continued (PDD-M) and discontinued (PDD-NM) anti-diabetic drug use after dialysis.

RESULTS

A total of 5249 dialysis patients were examined. The PDD-NM group displayed a significantly higher mortality rate than the IDD, PDD-M, and NDD groups (log-rank test P < 0.001). The PDD-M group had a significantly lower risk of death, regardless of insulin (P < 0.001) or oral hypoglycemic agent (OHA) (P < 0.001) use. Initial insulin administration or OHA had no statistically significant effect on overall mortality in the IDD group. But OHA use had better survival trends than insulin administration for the older (P = 0.02) and male subgroups (P = 0.05).

CONCLUSIONS

For dialysis patients with diabetes, continuous administration of anti-diabetic drugs after dialysis and choice of medication may affect outcomes.

Prevention of Hypertensive Disorders of Pregnancy-Is There a Place for Metformin?

The possibility of prophylaxis of hypertensive disorders of pregnancy (HDPs) such as preeclampsia (PE) and pregnancy-induced hypertension is of interest due to the unpredictable course of these diseases and the risks they carry for both mother and fetus. It has been proven that their development is associated with the presence of the placenta, and the processes that initiate it begin at the time of the abnormal invasion of the trophoblast in early pregnancy. The ideal HDP prophylaxis should alleviate the influence of risk factors and, at the same time, promote physiological trophoblast invasion and maintain the physiologic endothelium function without any harm to both mother and fetus. So far, aspirin is the only effective and recommended pharmacological agent for the prevention of HDPs in high-risk groups. Metformin is a hypoglycemic drug with a proven protective effect on the cardiovascular system. Respecting the anti-inflammatory properties of metformin and its favorable impact on the endothelium, it seems to be an interesting option for HDP prophylaxis. The results of previous studies on such use of metformin are ambiguous, although they indicate that in a certain group of pregnant women, it might be effective in preventing hypertensive complications. The aim of this study is to present the possibility of metformin in the prevention of hypertensive disorders of pregnancy with respect to its impact on the pathogenic elements of development

Anti-inflammatory Effects of Empagliflozin and Gemigliptin on LPS-Stimulated Macrophage via the IKK/NF-κB, MKK7/JNK, and JAK2/STAT1 Signalling Pathways

Background

Sodium-glucose cotransporter 2 (SGLT2) and dipeptidyl peptidase-4 (DPP-4) inhibitors are glucose-lowering drugs whose anti-inflammatory properties have recently become useful in tackling metabolic syndromes in chronic inflammatory diseases, including diabetes and obesity. We investigated whether empagliflozin (SGLT2 inhibitor) and gemigliptin (DPP-4 inhibitor) improve inflammatory responses in macrophages, identified signalling pathways responsible for these effects, and studied whether the effects can be augmented with dual empagliflozin and gemigliptin therapy.

Methods

RAW 264.7 macrophages were first stimulated with lipopolysaccharide (LPS), then cotreated with empagliflozin, gemigliptin, or empagliflozin plus gemigliptin. We conducted quantitative RT-PCR (qRT-PCR) to determine the most effective anti-inflammatory doses without cytotoxicity. We performed ELISA and qRT-PCR for inflammatory cytokines and chemokines and flow cytometry for CD80, the M1 macrophage surface marker, to evaluate the anti-inflammatory effects of empagliflozin and gemigliptin. NF-κB, MAPK, and JAK2/STAT signalling pathways were examined via Western blotting to elucidate the molecular mechanisms of anti-inflammation.

Results

LPS-stimulated CD80⁺ M1 macrophages were suppressed by coincubation with empagliflozin, gemigliptin, and empagliflozin plus gemigliptin, respectively. Empagliflozin and gemigliptin (individually and combined) inhibited prostaglandin E₂ (PGE₂) release and COX-2, iNOS gene expression in LPS-stimulated RAW 264.7 macrophages. These three treatments also attenuated the secretion and mRNA expression of proinflammatory cytokines, such as TNF-α, IL-1β, IL-6, and IFN-γ, and proinflammatory chemokines, such as CCL3, CCL4, CCL5, and CXCL10. All of them blocked NF-κB, JNK, and STAT1/3 phosphorylation through IKKα/β, MKK4/7, and JAK2 signalling.

Conclusions

Our study demonstrated the anti-inflammatory effects of empagliflozin and gemigliptin via IKK/NF-κB, MKK7/JNK, and JAK2/STAT1 pathway downregulation in macrophages. In all cases, combined empagliflozin and gemigliptin treatment showed greater anti-inflammatory properties.

Insulin Signaling in Arthritis

Inflammatory arthritis is burdened by an increased risk of metabolic disorders. Cytokines and other mediators in inflammatory diseases lead to insulin resistance, diabetes and hyperlipidemia. Accumulating evidence in the field of immunometabolism suggests that the cause-effect relationship between arthritis and metabolic abnormalities might be bidirectional. Indeed, the immune response can be modulated by various factors such as environmental agents, bacterial products and hormones. Insulin is produced by pancreatic cells and regulates glucose, fat metabolism and cell growth. The action of insulin is mediated through the insulin receptor (IR), localized on the cellular membrane of hepatocytes, myocytes and adipocytes but also on the surface of T cells, macrophages, and dendritic cells. In murine models, the absence of IR in T-cells coincided with reduced cytokine production, proliferation, and migration. In macrophages, defective insulin signaling resulted in enhanced glycolysis affecting the responses to pathogens. In this review, we focalize on the bidirectional cause-effect relationship between impaired insulin signaling and arthritis analyzing how insulin signaling may be involved in the aberrant immune response implicated in arthritis and how inflammatory mediators affect insulin signaling. Finally, the effect of glucose-lowering agents on arthritis was summarized.

Repurposing metformin to treat age-related neurodegenerative disorders and ischemic stroke

Aging is a risk factor for major central nervous system (CNS) disorders. More specifically, aging can be inked to neurodegenerative diseases (NDs) because of its deteriorating impact on neurovascular unit (NVU). Metformin, a first line FDA-approved anti-diabetic drug, has gained increasing interest among researchers for its role in improving aging-related neurodegenerative disorders. Additionally, numerous studies have illustrated metformin's role in ischemic stroke, a cerebrovascular disorder in which the NVU becomes dysfunctional which can lead to permanent life-threatening disabilities. Considering metformin's beneficial preclinical actions on various disorders, and the drug's role in alleviating severity of these conditions through involvement in commonly characterized cellular pathways, we discuss the potential of metformin as a suitable drug candidate for repurposing in CNS disorders.

Comparison of the effect of glucose-lowering agents on the risk of atrial fibrillation: A network meta-analysis

BACKGROUND

Diabetes is associated with the progression of atrial fibrillation (AF) and atrial flutter (AFL). However, whether glucose-lowering agents could reduce AF/AFL remains unclear. We hypothesized that different glucose-lowering agents exhibit different characteristic effects on the risk of AF/AFL.

OBJECTIVES

The goals of this study were to evaluate the effect of different glucose-lowering agents and identify the optimal treatment that can reduce AF/AFL events in patients with diabetes.

METHODS

We searched PubMed, Embase, and the Cochrane Library from their inception to September 30, 2020. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used in this network meta-analysis. The primary end point of our study was AF or AFL. Only studies that reported AF/AFL as clinical end points with a follow-up period of at least 12 months were included. The results from trials were presented as odds ratios (ORs) with 95% confidence intervals (CIs). The results were pooled using a Bayesian random-effects model.

RESULTS

Five eligible studies (9 glucose-lowering agents, including thiazolidinedione, metformin, sulfonylurea, insulin, dipeptidyl peptidase-4 inhibitor, glucagon-like peptide-1 receptor agonist [GLP-1RA], sodium-glucose cotransporter 2 inhibitor, alpha-glucosidase inhibitor, and non-sulfonylurea) consisting of 263,583 patients with type 2 diabetes mellitus were included. Based on the pooled results, GLP-1RA significantly reduced AF/AFL events compared with metformin (OR 0.17; 95% CI 0.04-0.61), sulfonylurea (OR 0.23; 95% CI 0.07-0.73), insulin (OR 0.20; 95% CI 0.07-0.86), and non-sulfonylurea (OR 0.18; 95% CI 0.04-0.66).

CONCLUSION

Compared with other glucose-lowering agents, GLP-1RA could reduce the risk of AF/AFL in patients with diabetes.

Use of antidiabetic medications and risk of chronic obstructive pulmonary disease exacerbation requiring hospitalization: a disease risk score-matched nested case-control study

BACKGROUND

Exacerbation of chronic obstructive pulmonary disease (COPD) severely impacts the quality of life and causes high mortality and morbidity. COPD is involved with systemic and pulmonary inflammation, which may be attenuated with antidiabetic agents exerting anti-inflammatory effects. Real-world evidence is scant regarding the effects of antidiabetic agents on COPD exacerbation. Accordingly, we conducted a disease risk score (DRS)-matched nested case-control study to systemically assess the association between each class of oral hypoglycemic agents (OHAs) and risk of severe COPD exacerbation in a nationwide COPD population co-diagnosed with diabetes mellitus (DM).

METHODS

We enrolled 23,875 COPD patients receiving at least one OHA for management of DM by analyzing the Taiwan National Health Insurance claims database between January 1, 2000, and December 31, 2015. Cases of severe exacerbation were defined as those who had the first hospital admission for COPD. Each case was individually matched with four randomly-selected controls by cohort entry date, DRS (the estimated probability of encountering a severe COPD exacerbation), and COPD medication regimens using the incidence density sampling approach. Conditional logistic regressions were performed to estimate odds ratios (OR) of severe COPD exacerbation for each type of OHAs.

RESULTS

We analyzed 2700 cases of severe COPD exacerbation and 9272 corresponding controls after DRS matching. Current use of metformin versus other OHAs was associated with a 15% (adjusted OR [aOR], 0.85; 95% confidence interval [CI] 0.75-0.95) reduced risk of severe COPD exacerbation, whereas the reduced risk was not observed with other types of antidiabetic agents. When considering the duration of antidiabetic medication therapy, current use of metformin for 91-180 and 181-365 days was associated with a 28% (aOR, 0.72; 95% CI 0.58-0.89) and 37% (aOR, 0.63; 95% CI 0.51-0.77) reduced risk of severe COPD exacerbation, respectively. Similarly, 91-180 days of sulfonylureas therapy led to a 28% (aOR, 0.72; 95% CI 0.58-0.90) lower risk, and longer treatments consistently yielded 24-30% lower risks. Current use of thiazolidinediones for more than 181 days yielded an approximately 40% decreased risk.

CONCLUSIONS

Duration-dependent beneficial effects of current metformin, sulfonylurea, and thiazolidinedione use on severe COPD exacerbation were observed in patients with COPD and DM.

Evaluation of the Effects of Acarbose on Weight and Metabolic, Inflammatory, and Cardiovascular Markers in Patients with Obesity and Overweight

Background:

Metabolic syndrome (MetS) refers to a cluster of risk factors for cardiovascular disease and type 2 diabetes. The aim of this study is to assess the effects of acarbose as an antihyperglycemic agent (drug) on late complications of MetS.

Methods:

This double-blind randomized clinical trial was done on patients with MetS admitted to Isfahan Endocrine and Metabolism Research Center. They were assigned randomly to two groups: A who received acarbose (n = 32) and group B who received a placebo (n = 42) for 6 months. Cardiovascular indexes including flow-mediated dilation (FMD), intima-media thickness (IMT), epicardial fat thickness (EFT), and C-reactive protein (CRP) were measured at baseline and 6 months after the treatment and compared between the two groups.

Results:

Post-intervention mean of weight (mean difference: −2.5 ± 0.89) and abdominal obesity (mean difference: −2.2 ± 0.64) in acarbose group were significantly decreased (P value < 0.001). High-density lipoprotein (HDL) level in acarbose group was significantly higher than control group (44.7 ± 7.6 vs 41.1 ± 6.4; P value = 0.043), while the other metabolic parameters were not significantly different between the two groups (P value > 0.05). In both groups, CRP and EFT decreased significantly after the intervention, and the levels of CRP, EFT, and IMT markers in the acarbose group were significantly lower than control group (P value < 0.05).

Conclusions:

The administration of acarbose in patients with MetS can decrease weight and abdominal obesity as well as the reduction of inflammatory and cardiovascular markers, including CRP, EFT, and IMT and also increases HDL.

The roles of PPARγ and its agonists in autoimmune diseases: A comprehensive review

Autoimmune diseases are common diseases of the immune system that are characterized by the loss of self-tolerance and the production of autoantibodies; the breakdown of immune tolerance and the prolonged inflammatory reaction are undisputedly core steps in the initiation and maintenance of autoimmunity. Peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors that belong to the nuclear hormone receptor family and act as ligand-activated transcription factors. There are three different isotypes of PPARs: PPARα, PPARγ, and PPARβ/δ. PPARγ is an established regulator of glucose homeostasis and lipid metabolism. Recent studies have demonstrated that PPARγ exhibits anti-inflammatory and anti-fibrotic effects in multiple disease models. PPARγ can also modulate the activation and polarization of macrophages, regulate the function of dendritic cells and mediate T cell survival, activation, and differentiation. In this review, we summarize the signaling pathways and biological functions of PPARγ and focus on how PPARγ and its agonists play protective roles in autoimmune diseases, including autoimmune thyroid diseases, multiple sclerosis, rheumatoid arthritis, systemic sclerosis, systemic lupus erythematosus, primary Sjogren syndrome and primary biliary cirrhosis.

Modulation of inflammatory pathways, medicinal uses and toxicities of Uvaria species: potential role in the prevention and treatment of inflammation

The therapeutic efficacy of the contemporary anti-inflammatory drugs are well established; however, prolonged use of such can often lead to serious and life-threatening side effects. Natural product-based anti-inflammatory compounds with superior efficacy and minimum toxicity can serve as possible therapeutic alternatives in this scenario. Genus Uvaria is a part of Annonaceae family, while the majority of its species are widely distributed in tropical rain forest regions of South East Asia. Uvaria species have been used extensively used as traditional medicine for treating all sorts of inflammatory diseases including catarrhal inflammation, rheumatism, acute allergic reactions, hemorrhoids, inflammatory liver disease and inflamed joints. Phytochemical analysis of Uvaria species has revealed flavones, flavonoids, tannins, saponins, polyoxygenated cyclohexene and phenolic compounds as major phyto-constituents. This review is an attempt to highlight the anti-inflammatory activity of Uvaria species by conducting a critical appraisal of the published literature. The ethnopharmacological relevance of Uvaria species in the light of toxicological studies is also discussed herein. An extensive and relevant literature on anti-inflammatory activity of Uvaria species was collected from available books, journals and electronic databases including PubMed, ScienceDirect, Scopus, Proquest and Ovid. Extracts and isolates of Uvaria species exhibited significant anti-inflammatory activity through various mechanisms of action. 6,7-di-O-Methyl-baicalein, flexuvarol B, chrysin, (-)-zeylenol, 6-hydroxy-5,7-dimethoxy-flavone, and pinocembrin were the most potent anti-inflammatory compounds with comparable IC₅₀ with positive controls. Therefore, it is suggested that further research should be carried out to determine the pharmacokinetics, pharmacodynamics and toxicity of these therapeutically significant compounds, to convert the pre-clinical results into clinical data for drug development and design.

Carotid Intima-Media Thickness Progression as Surrogate Marker for Cardiovascular Risk: Meta-Analysis of 119 Clinical Trials Involving 100 667 Patients

BACKGROUND

To quantify the association between effects of interventions on carotid intima-media thickness (cIMT) progression and their effects on cardiovascular disease (CVD) risk.

METHODS

We systematically collated data from randomized, controlled trials. cIMT was assessed as the mean value at the common-carotid-artery; if unavailable, the maximum value at the common-carotid-artery or other cIMT measures were used. The primary outcome was a combined CVD end point defined as myocardial infarction, stroke, revascularization procedures, or fatal CVD. We estimated intervention effects on cIMT progression and incident CVD for each trial, before relating the 2 using a Bayesian meta-regression approach.

RESULTS

We analyzed data of 119 randomized, controlled trials involving 100 667 patients (mean age 62 years, 42% female). Over an average follow-up of 3.7 years, 12 038 patients developed the combined CVD end point. Across all interventions, each 10 μm/y reduction of cIMT progression resulted in a relative risk for CVD of 0.91 (95% Credible Interval, 0.87-0.94), with an additional relative risk for CVD of 0.92 (0.87-0.97) being achieved independent of cIMT progression. Taken together, we estimated that interventions reducing cIMT progression by 10, 20, 30, or 40 μm/y would yield relative risks of 0.84 (0.75-0.93), 0.76 (0.67-0.85), 0.69 (0.59-0.79), or 0.63 (0.52-0.74), respectively. Results were similar when grouping trials by type of intervention, time of conduct, time to ultrasound follow-up, availability of individual-participant data, primary versus secondary prevention trials, type of cIMT measurement, and proportion of female patients.

CONCLUSIONS

The extent of intervention effects on cIMT progression predicted the degree of CVD risk reduction. This provides a missing link supporting the usefulness of cIMT progression as a surrogate marker for CVD risk in clinical trials.

A Triple-Blind Randomized Controlled Trial on Impacts of Pioglitazone on Oxidative Stress Markers in Diabetic Kidney Transplant Recipients

Background: Oxidative stress as a major mediator of adverse outcomes in kidney transplant recipients who are prone to oxidative stress-mediated injury by pre-transplant and post-transplant conditions. Objectives: The purpose of this study was to assess the effects of Pioglitazone on oxidative stress biomarkers and blood glucose control in diabetic patients receiving insulin after kidney transplantation. Methods: In a triple-blind randomized placebo-controlled trial, sixty-two kidney transplanted diabetic patients (40 men and 24 women) were followed for 4 months after randomly assigned to the placebo group and Pioglitazone group (30 mg/d). All of the patients continued their insulin therapy irrespective of the group that they were assigned to evaluate the effects of the addition of pioglitazone on blood glucose and oxidative stress biomarkers, Malondialdehyde (MDA) and total protein carbonyls (TPC) serum levels. Results: At baseline, there were no statistically significant differences in glycemic control levels and oxidative markers between the two groups. After 4 months of intervention, a significant improvement occurred in Hemoglobin A1c (HBA1c) in the Pioglitazone group. The changes of HBA1c during 4 months of follow up in the Pioglitazone group show improvement in glucose control were as HBA1c in the placebo group increased by 0.3% (P = 0.0001). Moreover, at the end of the study, the MDA level was significantly lower in the Pioglitazone group (P < 0.0001, 1.22 - 3.90). Regarding the serum level of TPC, the changes were not statistically different at baseline and also at the end of the study between two groups. Conclusions: Administration of Pioglitazone in addition to insulin in diabetic kidney transplant patients not only improved glycemic control (evidenced by HBA1c) but also significantly decreased oxidative stress markers such as MDA.

Restoration of β-Adrenergic Signaling and Activity of Akt-Kinase and AMP-Activated Protein Kinase with Metformin in the Myocardium of Diabetic Rats

We studied the effect of metformin (100 and 200 mg/kg/day, 4 weeks) on the adenylyl cyclasestimulating effects of β-agonists and relaxin in the myocardial membranes and on activities of Akt-kinase, an effector component of insulin signaling, and AMP-activated protein kinase (AMPK), a cellular energy sensor, in the myocardium of rats with type 2 diabetes mellitus induced by high-fat diet and streptozotocin. Metformin normalized the ratio of adenylyl cyclase effects of β_1/2- and β₃-agonists in the myocardial membranes, that is reduced in DM2, and restored phosphorylation of Akt-kinase by Ser473 and AMPK by Thr172 in the myocardium of diabetic rats. The effect of metformin in a dose of 200 mg/kg/day was more pronounced. Thus, the cardioprotective effect of metformin is due to its ability to restore the adrenergic and insulin regulation in cardiomyocytes and their energy status.

Reinterpreting Cardiorenal Protection of Renal Sodium-Glucose Cotransporter 2 Inhibitors via Cellular Life History Programming

Cardiovascular outcome trials have provided evidence that sodium-glucose cotransporter 2 inhibitor (SGLT2i) treatment is associated with remarkably favorable cardiovascular outcomes. Here, we offer a novel hypothesis that may encompass many of these hypothetical mechanisms, i.e., the ability of SGLT2i to modify the trajectory of cell response to a toxic environment through modifications of cellular life history programs, either the defense program or the dormancy program. The choice between these programs is mainly determined by the environment. Hyperglycemia can be considered a toxic determinant able to interfere with the basic programs of cell evolution. While the defense program is characterized by activation of the immune response and anabolic metabolism, the dormancy program is an energy-preserving state with high resistance to environmental stressors, and it has strong analogy with animal hibernation where fuel is stored, metabolic rate is suppressed, and insulin secretion is reduced. The metabolic changes that follow treatment with SGLT2i are reminiscent of the metabolic picture characteristic of the dormancy program. Therefore, we hypothesize that the beneficial cardioprotective effects of SGLT2i may be related to their ability to switch cell life programming from a defense to a dormancy state, thus lending additional benefit.

Characterization of glucose uptake metabolism in visceral fat by 18 F-FDG PET/CT reflects inflammatory status in metabolic syndrome

Objective

The inflammatory activity of visceral adipose tissue (VAT) is elevated in metabolic syndrome (MS), and associated with vulnerability to atherosclerosis. Inflammation can be assessed by glucose uptake in atherosclerotic plaques. We investigated whether the glucose uptake of VAT, assessed by ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT), is associated with systemic inflammatory status, and related to the number of MS components.

Methods

¹⁸F-FDG PET/CT was performed in a total of 203 participants: 59 without MS component; M(0), 92 with one or two MS components; M(1–2), and 52 with MS. Glucose uptake in VAT was evaluated using the mean standardized uptake value (SUVmean) and the maximum SUV (SUVmax). Glucose uptakes of immune-related organs such as the spleen and bone marrow (BM) were evaluated using the SUVmax.

Results

VAT SUVmax correlated with high-sensitivity C-reactive protein (hsCRP) and the SUVmax of spleen and BM, which reflect the status of systemic inflammation. Both hsCRP and the SUVmax of the spleen and BM were higher in the MS group than in the M(1–2) or M(0) groups. In VAT, SUVmax increased with increasing number of MS components, while SUVmean decreased.

Conclusions

The SUVmax and SUVmean of VAT assessed by ¹⁸F-FDG PET/CT reflected inflammation-driven unique glucose metabolism in the VAT of MS patients, distinct from that of atherosclerotic plaques.

Integral use of Argentinean Solanum betaceum red fruits as functional food ingredient to prevent metabolic syndrome: effect of in vitro simulated gastroduodenal digestion

The "red chilto" (Solanum betaceum Cav) is a native fruit from the Yungas forest of Argentina. Red chilto is a neglected and underutilized native species (NUS). The objective of this work was to evaluate the potentiality of pulp, seed and skin from "red chilto" as a functional food ingredient to add value to a native resource of Argentine Yungas to promote sustainable integral use of it. The powders have low carbohydrate and sodium content and are a source of vitamin C, phenolic acids (rosmarinic acid and caffeoylquinic acid), anthocyanins, condensed tannins, carotenoids, potassium, and fiber. The phenolics of chilto powders showed, before and after simulated gastroduodenal digestion, antioxidant activity (ABTS•+; H2O2; O2 •; HO•) and were able to inhibit enzymes related to metabolic syndrome, such as α-glucosidase, α-amylase and lipase. Chilto powder showed hypoglycemic effect by increasing glucose adsorption, decreasing glucose diffusion rate and by promoting glucose transport across the cell membrane. These results suggest the potential of Argentinean "red chilto" fruits as functional food ingredients or dietary supplements to prevent metabolic syndrome principally by its antioxidant, hypoglycemic and hypolipemic effects.

Cardioprotective anti-hyperglycaemic medications: a review of clinical trials

Despite extensive clinical efforts to achieve stricter glycaemic control over the past few decades, cardiovascular (CV) disease remains the leading cause of death among diabetic patients. Recently, sodium-glucose cotransporter-2 (SGLT-2) inhibitors and glucagon-like peptide-1 receptor (GLP-1-R) agonists have gained attention due to their apparent effects in reducing CV mortality. Four CV randomized controlled trials: EMPA-REG, CANVAS, LEADER, and SUSTAIN-6, found a decrease in CV events among patients with type 2 diabetes on empagliflozin, canagliflozin, liraglutide, and semaglutide, respectively. In light of this data, the US Food and Drug Administration has recently approved empagliflozin for CV mortality reduction in type 2 diabetic patients, making it the first diabetes medication approved for such an indication. The purpose of this review is to summarize the results of novel anti-hyperglycaemic medication trials, and shed light on their mode of action and cardioprotective pathways.

Mediators of the Effects of Canagliflozin on Heart Failure in Patients With Type 2 Diabetes

OBJECTIVES

The purpose of this study was to explore potential mediators of the effects of canagliflozin on heart failure in the CANVAS Program (CANagliflozin cardioVascular Assessment Study; NCT01032629 and CANagliflozin cardioVascular Assessment Study-Renal; NCT01989754).

BACKGROUND

Canagliflozin reduced the risk of heart failure among patients with type 2 diabetes in the CANVAS Program. The mechanism of protection is uncertain.

METHODS

The percentages of mediating effects of 19 biomarkers were determined by comparing the hazard ratios for the effect of randomized treatment from an unadjusted model and from a model adjusting for the biomarker of interest. Multivariable analyses were used to assess the joint effects of biomarkers that mediated most strongly in univariable analyses.

RESULTS

Early changes after randomization in levels of 3 biomarkers (urinary albumin:creatinine ratio, serum bicarbonate, and serum urate) were identified as mediating the effect of canagliflozin on heart failure. Average post-randomization levels of 14 biomarkers (systolic blood pressure, low-density lipoprotein and high-density lipoprotein cholesterol, total cholesterol, urinary albumin:creatinine ratio, weight, body mass index, gamma glutamyltransferase, hematocrit, hemoglobin concentration, serum albumin, erythrocyte concentration, serum bicarbonate, and serum urate) were identified as significant mediators. Individually, the 3 biomarkers with the largest mediating effect were erythrocyte concentration (45%), hemoglobin concentration (43%), and serum urate (40%). In a parsimonious multivariable model, erythrocyte concentration, serum urate, and urinary albumin:creatinine ratio were the 3 biomarkers that maximized cumulative mediation (102%).

CONCLUSIONS

A diverse set of potential mediators of the effect of canagliflozin on heart failure were identified. Some mediating effects were anticipated, whereas others were not. The mediators that were identified support existing and novel hypothesized mechanisms for the prevention of heart failure with sodium glucose cotransporter 2 inhibitors.

Type 2 diabetes mellitus and osteoarthritis

OBJECTIVES

Type 2 diabetes mellitus (T2DM) and osteoarthritis (OA) are common diseases that frequently co-exist, along with overweight/obesity. While the mechanical impact of excess body weight on joints may explain lower limb OA, we sought to explore whether T2DM is linked to OA outside of excess weight and whether T2DM may play a role in OA pathophysiology. The consequence of T2DM on OA outcomes is a question of research interest.

METHODS

We conducted a critical review of the literature to explore the association between T2DM and OA, whether any association is site-specific for OA, and whether the presence of T2DM impacts on OA outcomes. We also reviewed the literature to assess the safety of anti-OA treatments in patients with T2DM.

RESULTS

T2DM has a pathogenic effect on OA through 2 major pathways involving oxidative stress and low-grade chronic inflammation resulting from chronic hyperglycemia and insulin resistance. T2DM is a risk factor for OA progression and has a negative impact on arthroplasty outcomes. Evidence is mounting for safety concerns with some of the most frequently prescribed anti-OA medications, including paracetamol, non-steroidal anti-inflammatory drugs, and corticosteroid injections, while other anti-OA medications may be safely prescribed in OA patients with T2DM, such as glucosamine and intra-articular hyaluronic acid.

CONCLUSIONS

Future research is needed to better understand whether diabetes control and prevention can modulate OA occurrence and progression. The selection of therapy to treat OA symptoms in patients with T2DM may require careful consideration of the evidence based to avoid untoward safety issues.

The antitumor properties of metformin and phenformin reflect their ability to inhibit the actions of differentiated embryo chondrocyte 1

Background

Differentiated embryo chondrocyte 1 (DEC1) is a helix-loop-helix transcription factor that directly binds to the class B E-box in target genes. DEC1 exerts both pro-survival and pro-apoptotic effects in a cell- and tissue-dependent manner. Its actions play role the progression of cancer remains unclear.

Methods

We first examined the functional roles of DEC1 using the transient promoter reporter assay. Then, the knockdown of DEC1 expression was performed with the short hairpin RNA strategy in HeLa and A2058 cancer cell lines to check the cell cycle and mitochondrial function profile using the flow cytometry and Seahorse assays. We later clarified the role of DEC1 in the tumorigenesis using the colony formation, anchorage-independent growth assay, and cellular proliferation analysis.

Results

In the present study, we tested two guanide-containing drugs, metformin and phenformin, and found that both exhibit cytotoxicity against HeLa cervical carcinoma and A2058 melanoma cells. This effect was mediated, at least in part, through activation of the AMPK pathway; degradation of important cellular proteins, such as DEC1 and p53; and suppression of mitochondrial function, colony formation, and anchorage-independent cell proliferation. Our results further suggest that the cytotoxicity of metformin and phenformin reflect the impact of the repressive actions of DEC1 on gene expression, including DEC1 itself. This in turn suppresses both anchorage-independent growth and cell proliferation.

Conclusion

These findings provide several lines of evidence suggesting that DEC1 activity contributes to tumorigenicity and that the antitumor properties of biguanides reflect their ability to inhibit DEC1 functions.

Metformin in breast cancer: preclinical and clinical evidence

Metformin, a well-acknowledged biguanide, safety profile and multiaction drug with low cost for management of type 2 diabetes, makes a first-class candidate for repurposing. The off-patent drug draws huge attention for repositioned for anticancer drug delivery recently. Still few unanswered questions are challenging, among them one leading question; can metformin use as a generic therapy for all breast cancer subtypes? And is metformin able to get over the problem of drug resistance? The review focused on the mechanisms of metformin action specifically for breast cancer therapy and overcoming the resistance; also discusses preclinical and ongoing and completed clinical trials. The existing limitation such as therapeutic dose specifically for cancer treatment, resistance of metformin in breast cancer and organic cation transporters heterogeneity of the drug opens up a new pathway for improved understanding and successful application as repurposed effective chemotherapeutics for breast cancer. However, much more additional research is needed to confirm the accurate efficacy of metformin treatment for prevention of cancer and its recurrence.

Dipeptidyl dipeptidase-4 inhibitor recovered ischemia through an increase in vasculogenic endothelial progenitor cells and regeneration-associated cells in diet-induced obese mice

Metabolic syndrome (MS), overlapping type 2 diabetes, hyperlipidemia, and/or hypertension, owing to high-fat diet, poses risk for cardiovascular disease. A critical feature associated with such risk is the functional impairment of endothelial progenitor cells (EPCs). Dipeptidyl dipeptidase-4 inhibitors (DPP-4 i) not only inhibit degradation of incretins to control blood glucose levels, but also improve EPC bioactivity and induce anti-inflammatory effects in tissues. In the present study, we investigated the effects of such an inhibitor, MK-06266, in an ischemia model of MS using diet-induced obese (DIO) mice. EPC bioactivity was examined in MK-0626-administered DIO mice and a non-treated control group, using an EPC colony-forming assay and bone marrow cKit⁺ Sca-1⁺ lineage-cells, and peripheral blood-mononuclear cells. Our results showed that, in vitro, the effect of MK-0626 treatment on EPC bioactivities and differentiation was superior compared to the control. Furthermore, microvascular density and pericyte-recruited arteriole number increased in MK-0626-administered mice, but not in the control group. Lineage profiling of isolated cells from ischemic tissues revealed that MK-0626 administration has an inhibitory effect on unproductive inflammation. This occurred via a decrease in the influx of total blood cells and pro-inflammatory cells such as neutrophils, total macrophages, M1, total T-cells, cytotoxic T-cells, and B-cells, with a concomitant increase in number of regeneration-associated cells, such as M2/M ratio and T_reg/T-helper. Laser Doppler analysis revealed that at day 14 after ischemic injury, blood perfusion in hindlimb was greater in MK-0626-treated DIO mice, but not in control. In conclusion, the DPP-4 i had a positive effect on EPC differentiation in MS model of DIO mice. Following ischemic injury, DPP-4 i sharply reduced recruitment of pro-inflammatory cells into ischemic tissue and triggered regeneration and reparation, making it a promising therapeutic agent for MS treatment.

Beneficial effects of SGLT2 inhibitors on fatty liver in type 2 diabetes: A common comorbidity associated with severe complications

Patients with type 2 diabetes mellitus (T2DM) are exposed to non-alcoholic fatty liver disease (NAFLD), a comorbidity associated with cardiovascular disease and chronic kidney disease, and which may progress to non-alcoholic steatohepatitis (NASH), fibrosis and cirrhosis. Sodium-glucose cotransporter type-2 (SGLT2) inhibitors are glucose-lowering agents that improve glucose control while promoting weight loss and lowering serum uric acid levels. These agents may exert cardiovascular and renal protection in T2DM patients with established cardiovascular disease. Recent findings from both randomized controlled trials and open-label studies have also shown that SGLT2 inhibitors are able to reduce fatty liver content, as assessed by different imaging techniques, and improve biological markers of NAFLD, especially serum liver enzymes, in patients with T2DM. In addition, there are emerging data to suggest a mechanism beyond the reduction of hyperglycaemia and body weight, and a potential role for the decrease in low-grade inflammation and oxidative stress associated with SGLT2 inhibitor therapy. This positive effect of SGLT2 inhibitors on NAFLD complements their already well-known effects on cardiovascular and chronic kidney diseases.

Ameliorative Effects of Helianthus Annuus Against Nephrotoxic, Cardiac, and Haematological Disorders in Alloxan-induced Hyperglycaemia in Albino Rats

Introduction

The study evaluated the ameliorative effects of Helianthus annuus leaf extract on nephrotoxicity, cardiac, and haematologic disorders in alloxan-induced hyperglycaemic rats.

Material and Methods

The cold maceration method with 80% methanol was used in the preparation of H. annuus extract. Thirty alloxan-induced hyperglycaemic rats were randomly assigned to five equal groups (A–E). Groups A and B received 5% tween-20 solution in water (5 mL/kg) and glibenclamide (2 mg/kg), respectively; while groups C, D, and E received 150, 300, and 600 mg/kg of the extract, respectively, per os once daily for 21 consecutive days. The levels of serum urea, creatinine, haematological indices, and histopathological changes in the kidneys and heart were evaluated 24 h after the last treatment on day 21.

Results

The extract and glibenclamide significantly (P < 0.05) reduced the levels of serum urea and urea : creatinine ratio in diabetic rats when compared with the vehicle treated group. The extract and glibenclamide also ameliorated haematological disorders and kidney and cardiac damage induced by alloxan.

Conclusion

H. annuus extract produced nephroprotective, cardioprotective, and haematoprotective effects and might prevent the advancement of diabetic complications such as diabetic nephropathy and cardiovascular diseases in diabetic patients.