Canagliflozin protects against non-alcoholic steatohepatitis in type-2 diabetic rats through zinc alpha-2 glycoprotein up-regulation

The cellular and molecular mechanisms mediating the protective effects of sodium-glucose linked transporter 2 inhibitors against metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD), formerly known as nonalcoholic fatty liver disease (NAFLD), is a common, highly heterogeneous condition that affects about a quarter of the world's population, with no approved drug therapy. Current evidence from preclinical research and a number of small clinical trials indicates that SGLT2 inhibitors could also be effective for MAFLD. MAFLD is associated with a higher risk of chronic liver disease and multiple extrahepatic events, especially cardiovascular disease (CVD) and chronic kidney disease (CKD). MAFLD is considered a more appropriate terminology than NAFLD because it captures the complex bidirectional interplay between fatty liver and metabolic dysfunctions associated with disease progression, such as obesity and type 2 diabetes mellitus (T2DM). SGLT2 inhibitors are antidiabetic drugs that block glucose reabsorption in the kidney proximal tubule. In this article, we reviewed current clinical evidence supporting the potential use of SGLT2 inhibitors as a drug therapy for MAFLD and discussed the possible cellular and molecular mechanisms involved. We also reviewed the clinical benefits of SGLT2 inhibitors against MAFLD-related comorbidities, especially CVD, CKD and cardiovascular-kidney-metabolic syndrome (CKM). The broad beneficial effects of SGLT2 inhibitors support their use, likely in combination with other drugs, as a therapy for MAFLD.

Canagliflozin attenuates neurodegeneration and ameliorates dyskinesia through targeting the NLRP3/Nurr1/GSK-3β/SIRT3 pathway and autophagy modulation in rotenone-lesioned rats

Despite a deep understanding of Parkinson's disease (PD) and levodopa-induced dyskinesia (LID) pathogenesis, current therapies are insufficient to effectively manage the progressive nature of PD or halt LID. Growing hypotheses suggested the NOD-like receptor 3 (NLRP3) inflammasome and orphan nuclear receptor-related 1 (Nurr1)/glycogen synthase kinase-3β (GSK-3β) and peroxisome proliferator-activated receptor γ (PPARγ) coactivator-1α (PGC-1α)/sirtuin 3 (SIRT3) pathways as potential avenues for halting neuroinflammation and oxidative stress in PD.

AIMS

This study investigated for the first time the neuroprotective effect of canagliflozin against PD and LID in rotenone-intoxicated rats, emphasizing the crosstalk among the NLRP3/caspase-1 cascade, PGC-1α/SIRT3 pathway, mammalian target of rapamycin (mTOR)/beclin-1, and Nurr1/β-catenin/GSK-3β pathways as possible treatment strategies in PD and LID. Also, correlating NLRP3 expression with all evaluated parameters.

MAIN METHODS

The PD rat model was induced via eleven rotenone (1.5 mg/kg) subcutaneous injections day after day. Canagliflozin (20 mg/kg) and/or L-dopa/carbidopa (100/25 mg/kg) were orally administered daily from the beginning until the end of the experiment.

KEY FINDINGS

Canagliflozin significantly improved neurobehavioral and histological assessments, whereas dyskinesia scores declined. The improvement was confirmed through tyrosine hydroxylase and β-catenin upregulation in contrast to NLRP3 and caspase-1 in substantia nigra pars compacta, as revealed immunohistochemically. In addition, canagliflozin induced a prominent elevation in dopamine, Nurr1, PGC-1α, SIRT3, and beclin-1, whereas mTOR and GSK-3β expressions were downregulated.

SIGNIFICANCE

Our results revealed the aspiring canagliflozin neuroprotective properties against PD and LID in rotenone-lesioned rats via the assumed anti-inflammatory activity and implication of NLRP3/caspase-1, Nurr1/GSK-3β/β-catenin, PGC-1α/SIRT3, and beclin-1/mTOR pathways.

Targeting Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD): Available and Future Pharmaceutical Options

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects an ever-increasing part of the global population, affecting millions of individuals worldwide. Despite the progress in the treatment of other liver diseases, there is a scarcity of liver-specific drugs targeting MASLD. In light of that, research has focused both on pipeline drugs targeting multiple different receptors implicated in the pathogenesis of the disease, as well as medications already approved for other indications, that might exert beneficial effects on MASLD. The fact that MASLD is associated with an increased prevalence of obesity and type 2 diabetes mellitus (T2DM) establishes a possible pathway with respect to already available pharmaceutical interventions for this group of patients, such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose co-transporter-2 inhibitors (SGLT2-is). Thus, the hitherto at hand, along with the upcoming members of these families, provide much-needed options for our arsenal. This review attempts to explore old and novel dimensions of the pharmaceutical treatment of MASLD in the continuous effort of the medical society to improve patient outcomes.

SGLT2 inhibitors ameliorate NAFLD in mice via downregulating PFKFB3, suppressing glycolysis and modulating macrophage polarization

Sodium-glucose co-transporter 2 (SGLT2) inhibitor (SGLT2i) is a novel class of anti-diabetic drug, which has displayed a promising benefit for non-alcoholic fatty liver disease (NAFLD). In this study, we investigated the protective effects of SGLT2i against NAFLD and the underlying mechanisms. The db/db mice and western diet-induced NAFLD mice were treated with dapagliflozin (1 mg·kg-1·d-1, i.g.) or canagliflozin (10 mg·kg-1·d-1, i.g.) for 8 weeks. We showed that the SGLT2i significantly improved NAFLD-associated metabolic indexes, and attenuated hepatic steatosis and fibrosis. Notably, SGLT2i reduced the levels of pro-inflammatory cytokines and chemokines, downregulated M1 macrophage marker expression and upregulated M2 macrophage marker expression in liver tissues. In cultured mouse bone marrow-derived macrophages and human peripheral blood mononuclear cell-derived macrophages, the SGLT2i (10, 20 and 40 μmol/L) significantly promoted macrophage polarization from M1 to M2 phenotype. RNA sequencing, Seahorse analysis and liquid chromatography-tandem mass spectrometry analysis revealed that the SGLT2i suppressed glycolysis and triggered metabolic reprogramming in macrophages. By using genetic manipulation and pharmacological inhibition, we identified that the SGLT2i targeted PFKFB3, a key enzyme of glycolysis, to modulate the macrophage polarization of M1 to M2 phenotype. Using a co-culture of macrophages with hepatocytes, we demonstrated that the SGLT2i inhibited lipogenesis in hepatocytes via crosstalk with macrophages. In conclusion, this study highlights a potential therapeutic application for repurposing SGLT2i and identifying a potential target PFKFB3 for NAFLD treatment.

Evaluating the potential impact of sodium-glucose cotransporter-2 inhibitor "canagliflozin" on the hepatic damage triggered by hypertension in rats

Hypertension (HTN) is a prevalent chronic disease. HTN and liver disease association is extensively noted. Thus, finding a medication that can alleviate HTN and its accompanying liver insult would be promising. This study investigated the potential impacts of canagliflozin "sodium-glucose cotransporter-2 inhibitor" on the liver of the Nω-nitro-L-arginine methyl ester (L-NAME)-induced HTN rat model. Twenty-four adult male rats were divided into four groups; negative control group, canagliflozin group, L-NAME group: 50 mg/kg of L-NAME was injected daily for 5 weeks and L-NAME + canagliflozin group: 1 week after L-NAME injection both L-NAME + canagliflozin (40 mg/kg) were given concomitantly daily for further 4 weeks. Liver functions, serum lipid profile, hepatic oxidative/nitrative stress biomarkers, gene expression of lipogenic enzymes, B-cell lymphoma 2 (Bcl2), and DNA fragmentation, were measured. Besides, hepatic histology and immunohistochemistry of nuclear factor kappa B (NF-κB) and endothelial nitric oxide synthase (eNOS) were assessed. Canagliflozin improved hepatic lipogenesis via the downregulation of fatty acid synthase (FAS) and transcriptional regulatory element binding protein 1c (SREBP1c) genes leading to an improved serum lipid profile. Further, canagliflozin modified the eNOS/inducible nitric oxide synthase (iNOS) pathway and decreased the NF-κB immunoreactivity besides restoring the oxidants-antioxidants balance; increased reduced glutathione concomitant with declined malondialdehyde. This improvement of the liver was mirrored by the significant restoration of liver architecture and confirmed by the preserved liver DNA content and upregulation of the antiapoptotic Bcl2 mRNA level and attenuation of the alanine transaminase, aspartate aminotransferase. In conclusion, canagliflozin is a promising anti-hypertensive and hepatic-supportive medication. RESEARCH HIGHLIGHTS: Canagliflozin's antioxidant, anti-inflammatory, anti-lipogenic, and antiapoptotic characteristics mitigate remote liver compromise caused by hypertension. Canagliflozin can be exploited as a hepatoprotective and antihypertensive medication.

Canagliflozin Pretreatment Attenuates Myocardial Dysfunction and Improves Postcardiac Arrest Outcomes After Cardiac Arrest and Cardiopulmonary Resuscitation in Mice

OBJECTIVE

The SGLT2 inhibitor, canagliflozin, not only reduces glycemia in patients with type 2 diabetes but also exerts cardioprotective effects in individuals without diabetes. However, its potential beneficial effects in cardiac arrest have not been characterized. The purpose of this study was to examine the protective effect of canagliflozin pretreatment on postresuscitation-induced cardiac dysfunction in vivo.

METHODS

Male C57/BL6 mice were randomized to vehicle (sham and control) or canagliflozin treatment groups. All mice except for the sham-operated mice were subjected to potassium chloride-induced cardiac arrest followed by chest compressions and intravenous epinephrine for resuscitation. Canagliflozin therapy efficacies were evaluated by electrocardiogram, echocardiography, histological analysis, inflammatory response, serum markers of myocardial injury, protein phosphorylation analysis, and immunohistological assessment.

RESULTS

Canagliflozin-pretreated mice exhibited a higher survival rate (P < 0.05), a shorter return of spontaneous circulation (ROSC) time (P < 0.01) and a higher neurological score (P < 0.01 or P < 0.001) than control mice after resuscitation. Canagliflozin was effective at improving cardiac arrest and resuscitation-associated cardiac dysfunction, indicated by increased left ventricular ejection fraction and fractional shortening (P < 0.001). Canagliflozin reduced serum levels of LDH, CK-MB and α-HBDH, ameliorated systemic inflammatory response, and diminished the incidence of early resuscitation-induced arrhythmia. Notably, canagliflozin promoted phosphorylation of cardiac STAT-3 postresuscitation. Furthermore, pharmacological inhibition of STAT-3 by Ag490 blunted STAT-3 phosphorylation and abolished the cardioprotective actions of canagliflozin.

CONCLUSIONS

Canagliflozin offered a strong cardioprotective effect against cardiac arrest and resuscitation-induced cardiac dysfunction. This canagliflozin-induced cardioprotection is mediated by the STAT-3-dependent cell-survival signaling pathway.

SGLT2 inhibitor empagliflozin downregulates miRNA-34a-5p and targets GREM2 to inactivate hepatic stellate cells and ameliorate non-alcoholic fatty liver disease-associated fibrosis

BACKGROUND AND RATIONALE

Activation of hepatic stellate cells (HSCs), the central event of fibrosis, indicates the severe stage of non-alcoholic fatty liver disease (NAFLD). MicroRNAs (miRNAs) participate in this process. Treatment with a sodium-glucose cotransporter 2 inhibitor (SGLT2i) alleviates liver fibrosis in patients with type 2 diabetes and NAFLD; however, the role of SGLT2i in ameliorating liver fibrosis in NAFLD by regulating miRNAs remains unclear.

APPROACH AND RESULTS

We monitored the expression of NAFLD-associated miRNAs in the livers of two NAFLD models and observed high expression of miR-34a-5p. miR-34a-5p was highly expressed in mouse primary liver non-parenchymal cells and LX-2 HSCs, and this miRNA was positively correlated with alanine transaminase levels in NAFLD models. Overexpression of miR-34a-5p enhanced LX-2 activation, whereas its inhibition prevented HSCs activation by regulating the TGFβ signaling pathway. The SGLT2i empagliflozin significantly downregulated miR-34a-5p, inhibited the TGFβ signaling pathway, and ameliorated hepatic fibrosis in NAFLD models. Subsequently, GREM2 was identified as a direct target of miR-34a-5p through database prediction and a dual-luciferase reporter assay. In LX-2 HSCs, the miR-34a-5p mimic and inhibitor directly downregulated and upregulated GREM2, respectively. Overexpressing GREM2 inactivated the TGFβ pathway whereas GREM2 knockdown activated it. Additionally, empagliflozin upregulated Grem2 expression in NAFLD models. In methionine- and choline-deficient diet-fed ob/ob mice, a fibrosis model, empagliflozin downregulated miR-34a-5p and upregulated Grem2 to improve liver fibrosis.

CONCLUSIONS

Empagliflozin ameliorates NAFLD-associated fibrosis by downregulating miR-34a-5p and targeting GREM2 to inhibit the TGFβ pathway in HSCs.

Canagliflozin attenuates thioacetamide-induced liver injury through modulation of HMGB1/RAGE/TLR4 signaling pathways

Thioacetamide (TAA), a classic liver toxic compound, is used to establish experimental models of liver injury via induction of inflammation and oxidative stress. The current study was employed to explore the effects of canagliflozin (CANA), a sodium glucose cotransporter 2 (SGLT-2) inhibitor and antidiabetic agent, on TAA-induced acute liver injury.

METHODS

A rat model of acute hepatic injury was established using single intraperitoneal injection of TAA (500 mg/kg) and rats received CANA (10 and 30 mg/kg, orally) once daily for 10 days prior to TAA challenge. Liver function, oxidative stress, and inflammatory parameters were measured in serum and hepatic tissues of rats.

RESULTS

Elevated levels of liver enzymes, hepatic malondialdehyde (MDA), and serum lactate dehydrogenase (LDH) were significantly attenuated by CANA. CANA also increased hepatic superoxide dismutase (SOD) and glutathione (GSH). Hepatic levels of high-mobility group box 1 (HMGB1), toll like receptor4 (TLR4), receptor for advanced glycation end products (RAGE), and pro-inflammatory cytokines (IL-6, and IL-1β) were normalized with CANA. Additionally, Hepatic expression of p-JNK/p-p38 MAPK was significantly attenuated by CANA compared to TAA-treated rats. CANA also decreased hepatic immunoexpression of NF-κB and TNF-α and attenuated hepatic histopathological alterations via reduction of inflammation and necrosis scores and collagen deposition. Moreover, mRNA expression levels of TNF-α and IL-6 were reduced upon CANA treatment.

CONCLUSION

CANA attenuates TAA-prompted acute liver damage, via suppressing HMGB1/RAGE/TLR4 signaling, regulation of oxidative stress and inflammation pathways.

Current, emerging, and potential therapies for non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) has been identified as the most common chronic liver disease worldwide, with a growing incidence. NAFLD is considered the hepatic manifestation of a metabolic syndrome that emerges from multiple factors (e.g., oxidative stress, metabolic disorders, endoplasmic reticulum stress, cell death, and inflammation). Non-alcoholic steatohepatitis (NASH), an advanced form of NAFLD, has been reported to be a leading cause of cirrhosis and hepatic carcinoma, and it is progressing rapidly. Since there is no approved pharmacotherapy for NASH, a considerable number of therapeutic targets have emerged with the deepening of the research on NASH pathogenesis. In this study, the therapeutic potential and properties of regulating metabolism, the gut microbiome, antioxidant, microRNA, inhibiting apoptosis, targeting ferroptosis, and stem cell-based therapy in NASH are reviewed and evaluated. Since the single-drug treatment of NASH is affected by individual heterogeneous responses and side effects, it is imperative to precisely carry out targeted therapy with low toxicity. Lastly, targeted therapeutic agent delivery based on exosomes is proposed in this study, such that drugs with different mechanisms can be incorporated to generate high-efficiency and low-toxicity individualized medicine.

Zinc Alpha 2 Glycoprotein as an Early Biomarker of Diabetic Nephropathy in Type 2 Diabetes Mellitus Patients

Background and objectives Microalbuminuria is an early sign of diabetic nephropathy (DN). However, pathological abnormalities occur before the onset of microalbuminuria. Renal impairment progresses in about 50% of cases in type 2 diabetes mellitus (T2DM) without significant albuminuria. Diabetes mellitus (DM) is linked with obesity, metabolic syndrome, and lifestyle changes, where adipokines play an important role. Zinc alpha 2 glycoprotein (ZAGP) is an adipokine, and in this study, it was assessed as a potential biomarker for early DN as well as its progression. Materials and methods This study was a cross-sectional case-control study conducted at a tertiary hospital in northern India. T2DM patients aged 18-65 years old were included in the study and were divided into four groups based on their albuminuria level. This study included 160 participants, with 40 participants in each group. Group I included healthy volunteers, while Groups II, III, and IV were normoalbuminuric, microalbuminuric, and macroalbuminuric diabetic patients, respectively. The groups were evaluated for demographic variables, biochemical parameters, urine albumin-creatinine ratio (UACR), and serum ZAGP. Data between the groups were compared statistically. Results This study included 160 participants, with 40 participants in each group. There was a significant difference between the groups based on the serum ZAGP (p<0.001). Serum ZAGP was significantly negatively correlated with serum creatinine, glycosylated hemoglobin (HbA1c), serum cholesterol, serum triglyceride, low-density lipoprotein (LDL) cholesterol, and UACR. ZAGP was positively correlated with the estimated glomerular filtration rate (eGFR). Conclusion The present study showed that ZAGP was an early biomarker of diabetic nephropathy, and its value decreased as DN progressed. It also suggested that ZAGP, an adipokine, has an anti-inflammatory mechanism of action and its depletion worsens the disease.

Sodium-Glucose Cotransporter-2 Inhibition Exacerbates Hepatic Encephalopathy in Biliary Cirrhotic Rats

In liver cirrhosis, hepatic inflammation and abundant portal-systemic collaterals are indicated for the development of hepatic encephalopathy. Sodium-glucose cotransporter-2 (SGLT-2) inhibitors are a type of anti-diabetic agent which exert pleiotropic and anti-inflammatory effects. Diabetes and chronic liver disease often coexist, but the influence of SGLT-2 inhibition on liver cirrhosis and hepatic encephalopathy remains unknown. This study investigated the effect of SGLT-2 inhibition on cirrhotic rats. Biliary cirrhosis was induced in Sprague-Dawley rats via common bile duct ligation. A total of two weeks of treatment with the SGLT-2 inhibitor, empagliflozin 30 mg/kg/d, was applied. The motor activities, hemodynamics, biochemistry parameters, plasma levels of vascular endothelial growth factor (VEGF), and the severity of portal-systemic collateral shunts were measured. The hepatic histopathology and protein expressions were examined. We found that empagliflozin treatment did not affect hemodynamics, liver biochemistry, or blood glucose levels in cirrhotic rats. Empagliflozin did not affect hepatic inflammation and fibrosis. The protein expression of factors related to liver injury were not influenced by empagliflozin. However, empagliflozin decreased motor activities in cirrhotic rats and increased portal-systemic collateral shunts and VEGF plasma levels. In summary, SGLT-2 inhibition by empagliflozin did not ameliorate portal hypertension and hepatic inflammation in cirrhotic rats. In contrast, it exacerbated hepatic encephalopathy, which was evidenced by a decrease in motor activity. A possible mechanism could be an increase of portal-systemic shunts related to VEGF upregulation. Therefore, empagliflozin use should be cautious in cirrhotic patients regarding the development of hepatic encephalopathy. SIGNIFICANCE STATEMENT: Sodium-glucose cotransporter-2 inhibition by empagliflozin did not ameliorate portal hypertension and hepatic inflammation in cirrhotic rats. In contrast, it exacerbated hepatic encephalopathy through increased portal-systemic shunts related to VEGF up-regulation.

MCAD activation by empagliflozin promotes fatty acid oxidation and reduces lipid deposition in NASH

Medium-chain acyl-CoA dehydrogenase (MCAD) is one of the significant enzymes involved in the β-oxidation of mitochondrial fatty acids. MCAD deficiency affects the β-oxidation of fatty acid and leads to lipid deposition in multiple organs, but little is known about its importance in nonalcoholic steatohepatitis (NASH). Empagliflozin is revealed to effectively improve NASH by increasing research, whereas the specific mechanism still has to be explored. Human liver tissues of patients with or without NASH were obtained for proteomic analysis to screen proteins of interest. db/db mice were given empagliflozin by gavage for 8 weeks. The expression of MCAD and signaling molecules involved in hepatic lipid metabolism was evaluated in human liver, mice and HL7702 cells. We found that the MCAD levels in the liver were significantly reduced in NASH patients compared to patients without NASH. Protein-protein interaction network analysis showed that MCAD was highly correlated with forkhead box A2 (FOXA2) and protein kinase AMP-activated catalytic subunit alpha (PRKAA). AMPK/FOXA2/MCAD signaling pathway was detected to be inhibited in the liver of NASH patients. Decreased expression of MCAD was also observed in the livers of db/db mice and hepatocyte treated with palmitic acid and glucose. Of note, empagliflozin could upregulate MCAD expression by activating AMPK/FOXA2 signaling pathway, reduce lipid deposition and improve NASH in vivo and in vitro. This research demonstrated that MCAD is a key player of hepatic lipid deposition and its targeting partially corrects NASH. MCAD thus may be a potential therapeutic target for the treatment of NASH.

The impact of SGLT2 inhibitors on inflammation: A systematic review and meta-analysis of studies in rodents

BACKGROUND

Inhibition of sodium-glucose cotransporter-2 (SGLT2) has received remarkable attention due to the beneficial effects observed in diabetes mellitus, heart failure, and kidney disease. Several mechanisms have been proposed for these pleiotropic effects, including anti-inflammatory ones. Our systematic review and meta-analysis aimed to assess the effect of SGLT2 inhibition on inflammatory markers in experimental models.

METHODS

A literature search was conducted to detect studies examining the effect of SGLT2 inhibitors on inflammatory markers [interleukin-6 (IL-6), C reactive protein (CRP), tumor necrosis factor-α (TNF-α), and monocyte chemoattractant protein-1 (MCP-1)]. Consequently, a meta-analysis of the included studies was performed, assessing the differences in the levels of the inflammatory markers between the treatment groups as its primary outcome. Moreover, risk of bias, sensitivity analysis and publication bias were evaluated.

RESULTS

The systematic literature review yielded 30 studies whose meta-analysis suggested that treatment with an SGLT2 inhibitor resulted in decreases of IL-6 [standardized mean difference (SMD): -1.56, 95% CI -2.06 to -1.05), CRP (SMD: -2.17, 95% CI -2.80 to -1.53), TNF-α (SMD: -1.75, 95% CI -2.14 to -1.37), and MCP-1 (SMD: -2.04, 95% CI -2.91 to -1.17). The effect on CRP and TNF-α was of lesser magnitude in cases of empagliflozin use. Moderate-to-substantial heterogeneity and possible publication bias were noted. The findings remained largely unaffected after the sensitivity analyses, the exclusion of outlying studies, and trim-and-fill analyses.

CONCLUSION

The present meta-analysis suggests that SGLT2 inhibition results in reduction of inflammatory markers in animal models, further validating the suggested anti-inflammatory mechanism of action.

Canagliflozin Ameliorates Nonalcoholic Fatty Liver Disease by Regulating Lipid Metabolism and Inhibiting Inflammation through Induction of Autophagy

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is closely associated with metabolic diseases, including obesity and diabetes, and has gradually become the most common cause of chronic liver disease. We investigated the effects of sodium glucose cotransporter 2 (SGLT2) inhibitor canagliflozin on NAFLD in high-fat diet (HFD)-induced obese mice and possible underlying mechanisms.

MATERIALS AND METHODS

Male C57BL/6 mice were fed a normal-diet, HFD, or HFD with canagliflozin for 14 weeks. AML-12 hepatocytes were treated with canagliflozin. Expression of related pathways was assessed.

RESULTS

Canagliflozin administration reduced body weight and fat mass, compared with HFD alone. Canagliflozin improved glucose and lipid metabolic disorders. Compared with HFD-fed mice, liver weight, serum alanine transaminase (ALT) levels, and hepatic lipid accumulation were decreased after canagliflozin administration. Additionally, canagliflozin upregulated lipolysis markers (CPT1a, ACOX1, and ACADM), downregulated lipogenesis markers (SREBP-1c and FASN), and suppressed the production of inflammatory cytokines (TNFα, MCP1, IL-1β, and IL-6), consistent with significantly increased LC3 II/I and Atg7 levels in the liver following canagliflozin treatment. In vitro, canagliflozin increased CPT1a, ACOX1, and ACADM expression, decreased SREBP-1c and FASN protein expression, and reduced TNFα, MCP1, IL-1β, and IL-6 mRNA levels in lipid mixture (LM)-induced hepatocytes in a dose-dependent manner. These changes were reversed by 3-MA, an autophagy inhibitor.

CONCLUSION

Our findings suggest that canagliflozin ameliorates the pathogenesis of NAFLD by regulating lipid metabolism and inhibiting inflammation, which may be associated with its promotion of autophagy.

Empagliflozin-Enhanced Antioxidant Defense Attenuates Lipotoxicity and Protects Hepatocytes by Promoting FoxO3a- and Nrf2-Mediated Nuclear Translocation via the CAMKK2/AMPK Pathway

Lipotoxicity is an important factor in the development and progression of nonalcoholic steatohepatitis. Excessive accumulation of saturated fatty acids can increase the substrates of the mitochondrial electron transport chain in hepatocytes and cause the generation of reactive oxygen species, resulting in oxidative stress, mitochondrial dysfunction, loss of mitochondrial membrane potential, impaired triphosphate (ATP) production, and fracture and fragmentation of mitochondria, which ultimately leads to hepatocellular inflammatory injuries, apoptosis, and necrosis. In this study, we systematically investigated the effects and molecular mechanisms of empagliflozin on lipotoxicity in palmitic acid-treated LO2 cell lines. We found that empagliflozin protected hepatocytes and inhibited palmitic acid-induced lipotoxicity by reducing oxidative stress, improving mitochondrial functions, and attenuating apoptosis and inflammation responses. The mechanistic study indicated that empagliflozin significantly activated adenosine 5'-monophosphate (AMP)-activated protein kinase alpha (AMPKα) through Calcium/Calmodulin dependent protein kinase kinase beta (CAMKK2) instead of liver kinase B1 (LKB1) or TGF-beta activated kinase (TAK1). The activation of empagliflozin on AMPKα not only promoted FoxO3a phosphorylation and thus forkhead box O 3a (FoxO3a) nuclear translocation, but also promoted Nrf2 nuclear translocation. Furthermore, empagliflozin significantly upregulated the expressions of antioxidant enzymes superoxide dismutase (SOD) and HO-1. In addition, empagliflozin did not attenuate lipid accumulation at all. These results indicated that empagliflozin mitigated lipotoxicity in saturated fatty acid-induced hepatocytes, likely by promoting antioxidant defense instead of attenuating lipid accumulation through enhanced FoxO3a and Nrf2 nuclear translocation dependent on the CAMKK2/AMPKα pathway. The CAMKK2/AMPKα pathway might serve as a promising target in treatment of lipotoxicity in nonalcoholic steatohepatitis.

Indapamide Increases IRS1 Expression and Modifies Adiponectin/NLRP3/PPARγ Crosstalk in Type 2 Diabetic Rats

The current study aimed to evaluate the anti-diabetic effects of canagliflozin (CANA) and indapamide (INDA) and their impacts as adiponectin modulators in experimentally induced type 2 diabetes mellitus (T2DM). T2DM was associated with a significant rise in blood glucose level and HbA1C%, andreduced adiponectin and insulin secretions. Moreover, the malondialdehyde (MDA) contents in both the epididymal adipocytes and soleus muscle significantly escalated, while the total antioxidant capacity (TAC) and epididymal adipocyte Nrf2 expression significantly declined. Moreover, serum TNF-α, epididymal adipocyte’s NOD-like receptor protein 3, NLRP3, NF-κB and CD68 expressions markedly escalated, and serum IL-10 significantly declined. Furthermore, there was a significant escalation in PPARγ expression in epididymal adipocytes, with a significant reduction in soleus muscle’s expression of IRS1. CANA and INDA treatments markedly reduced blood glucose levels, increased adiponectin and insulin secretion, enhanced anti-oxidant defenses, and reduced oxidative burden, with marked anti-inflammatory impact. Interestingly, the impact of indapamide on DM indices and oxidative and inflammatory changes was comparable to that of canagliflozin. Nevertheless, indapamide had a superior effect compared to canagliflozin on HbA1c%, expression of IRS1 and reduction of NF-κB and CD68 expressions. INDA could be effective in regulating T2DM, with underlined anti-diabetic, antioxidant, and anti-inflammatory properties. INDA increased IRS1 expression and modified adiponectin/NLRP3/PPARγ crosstalk. The impacts of INDA are comparable to those of the standard anti-diabetic drug CANA.

SGLT-2 Inhibitors in NAFLD: Expanding Their Role beyond Diabetes and Cardioprotection

Non-alcoholic fatty liver disease (NAFLD) is an ‘umbrella’ term, comprising a spectrum ranging from benign, liver steatosis to non-alcoholic steatohepatitis, liver fibrosis and eventually cirrhosis and hepatocellular carcinoma. NAFLD has evolved as a major health problem in recent years. Discovering ways to prevent or delay the progression of NAFLD has become a global focus. Lifestyle modifications remain the cornerstone of NAFLD treatment, even though various pharmaceutical interventions are currently under clinical trial. Among them, sodium-glucose co-transporter type-2 inhibitors (SGLT-2i) are emerging as promising agents. Processes regulated by SGLT-2i, such as endoplasmic reticulum (ER) and oxidative stress, low-grade inflammation, autophagy and apoptosis are all implicated in NAFLD pathogenesis. In this review, we summarize the current understanding of the NAFLD pathophysiology, and specifically focus on the potential impact of SGLT-2i in NAFLD development and progression, providing current evidence from in vitro, animal and human studies. Given this evidence, further mechanistic studies would advance our understanding of the exact mechanisms underlying the pathogenesis of NAFLD and the potential beneficial actions of SGLT-2i in the context of NAFLD treatment.

SGLT2 Inhibition for Cardiovascular Diseases, Chronic Kidney Disease, and NAFLD

Sodium glucose cotransporter 2 (SGLT-2) inhibitors are the latest class of antidiabetic medications. They prevent glucose reabsorption in the proximal convoluted tubule to decrease blood sugar. Several animal studies revealed that SGLT-2 is profoundly involved in the inflammatory response, fibrogenesis, and regulation of numerous intracellular signaling pathways. Likewise, SGLT-2 inhibitors markedly attenuated inflammation and fibrogenesis and improved the function of damaged organ in animal studies, observational studies, and clinical trials. SGLT-2 inhibitors can decrease blood pressure and ameliorate hypertriglyceridemia and obesity. Likewise, they improve the outcome of cardiovascular diseases such as heart failure, arrhythmias, and ischemic heart disease. SGLT-2 inhibitors are associated with lower cardiovascular and all-cause mortality as well. Meanwhile, they protect against nonalcoholic fatty liver disease (NAFLD), chronic kidney disease, acute kidney injury, and improve micro- and macroalbuminuria. SGLT-2 inhibitors can reprogram numerous signaling pathways to improve NAFLD, cardiovascular diseases, and renal diseases. For instance, they enhance lipolysis, ketogenesis, mitochondrial biogenesis, and autophagy while they attenuate the renin-angiotensin-aldosterone system, lipogenesis, endoplasmic reticulum stress, oxidative stress, apoptosis, and fibrogenesis. This review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases and dissects the underlying molecular mechanisms in detail. This narrative review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases using the results of latest observational studies, clinical trials, and meta-analyses. Thereafter, it dissects the underlying molecular mechanisms involved in the clinical effects of SGLT-2 inhibitors on these diseases.

Proteomics Analysis of Serum Proteins in Gestational Diabetes

OBJECTIVE

The purpose of this study was to screen serum proteins for biomarkers of gestational diabetes mellitus (GDM) and to investigate its pathogenesis by analyzing the differences in serum proteomics between pregnant women with GDM and healthy pregnant women.

METHODS

Patients who were admitted to the First Affiliated Hospital of Fujian Medical University from June 2019 to January 2020 were included. According to the medical history and the results of the 75 g oral glucose tolerance test (OGTT), they were divided into the normal pregnant women group and GDM pregnant women group. The serum of two groups of patients was collected. High performance liquid chromatography-mass spectrometry was used to identify differentially expressed serum proteins between pregnant women with GDM and healthy pregnant women, and bioinformatics analysis was then performed on the identified proteins.

RESULTS

A total of 1152 quantifiable proteins were detected; among them, 15 were upregulated in serum of GDM pregnant women, while 26 were downregulated. The subsequent parallel reaction monitoring (PRM) assay validated the expression levels of 12 out of 41 differentially expressed proteins. Moreover, bioinformatics analysis revealed that the differentially expressed proteins are involved in multiple biological processes and signaling pathways related to the lipid metabolism, glycan degradation, immune response, and platelet aggregation.

CONCLUSIONS

This study identified 41 serum proteins with differential expression between pregnant women with GDM and healthy pregnant women, providing new candidate molecules for elucidating GDM pathogenesis and screening therapeutic targets.

Sodium-glucose co-transporter 2 inhibitors in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is considered the most prevalent chronic hepatic disease, as it has been estimated that one of four individuals in the general population has been affected by NAFLD. The evolution of the referred entity, which includes nonalcoholic steatohepatitis (NASH) and hepatic fibrosis, may have crucial and even fatal consequences, leading to cirrhosis and hepatocellular carcinoma. Although NAFLD has also been linked with cardiovascular and renal diseases, and all-cause mortality increment, pharmacological therapy is as yet an unfulfilled demand. Since NAFLD is closely associated with type 2 diabetes mellitus (T2DM), a variety of anti-diabetic drugs have been investigated for their effectiveness towards NAFLD. Sodium-glucose co-transporter 2 inhibitors (SGLT-2i) improve blood glucose levels through increasing renal glucose excretion and they are recommended as one of standard therapeutic categories for T2DM patients. Based on preclinical animal studies, SGLT-2i have shown a beneficial effect on NAFLD, inducing histologically proven amelioration of hepatic steatosis, inflammation and fibrosis. Promising data have been also derived by clinical trials, which have indicated a potentially beneficial effect of SGLT-2i on NAFLD, at least in terms of liver function tests and imaging. Thus, it is not strange that there are many ongoing trials on the effect of various SGLT-2i in NAFLD. In conclusion, current evidence concerning the effect of SGLT-2i on NAFLD is encouraging; however, data from ongoing clinical trials with histological endpoints are awaited.

Canagliflozin Improves Liver Function in Rats by Upregulating Asparagine Synthetase

INTRODUCTION

Canagliflozin (CANA) is a sodium-glucose cotransporter 2 inhibitor that was recently approved for treating diabetes. However, its effects on liver function are not well understood. The function of asparagine synthetase (ASNS) has been studied in several cancers but not in liver injury. Therefore, we investigated the connection between CANA and ASNS in alleviating damage (i.e., their hepatoprotective effect) in a rat liver injury model.

METHODS

The rat model of liver injury was established using carbon tetrachloride treatment. Rats with liver injury were administered CANA orally for 8 weeks daily. After week 8, peripheral blood was collected to measure serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels. Liver histopathology was examined using hematoxylin and eosin staining to determine the degree of liver injury. Protein expression in the rat livers was examined using Western blotting.

RESULTS

CANA treatment decreased serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels compared with those of the untreated group, demonstrating diminished liver injury. Mechanistically, CANA treatment activated AMP-activated protein kinase (AMPK), leading to increased nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and activating transcription factor 4 (ATF4), which upregulated ASNS expression in liver-injured rats.

CONCLUSION

CANA significantly alleviated liver injury by activating the AMPK/Nrf2/ATF4 axis and upregulating ASNS expression, indicating its potential for treating patients with type 2 diabetes mellitus with impaired liver function.

Emergence of SGLT2 Inhibitors as Powerful Antioxidants in Human Diseases

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of oral glucose-lowering agents. Apart from their glucose-lowering effects, large clinical trials assessing certain SGLT2 inhibitors have revealed cardiac and renal protective effects in non-diabetic patients. These excellent outcomes motivated scientists and clinical professionals to revisit their underlying mechanisms. In addition to the heart and kidney, redox homeostasis is crucial in several human diseases, including liver diseases, neural disorders, and cancers, with accumulating preclinical studies demonstrating the therapeutic benefits of SGLT2 inhibitors. In the present review, we aimed to update recent advances in the antioxidant roles of SGLT2 inhibitors in common but debilitating human diseases. We anticipate that this review will guide new research directions and novel therapeutic strategies for diabetes, cardiovascular diseases, nephropathies, liver diseases, neural disorders, and cancers in the era of SGLT2 inhibitors.

The association of the adipokine zinc-alpha2-glycoprotein with non-alcoholic fatty liver disease and related risk factors: A comprehensive systematic review

BACKGROUND AND AIM

The adipokine zinc-alpha2-glycoprotein (ZAG), a multidisciplinary protein, is involved in lipid metabolism, glucose homeostasis and energy balance. Accumulating evidence demonstrates that the expression of ZAG is mainly downregulated in obesity and obesity-related conditions. In the present study, we assessed the association of ZAG with non-alcoholic fatty liver disease (NAFLD) and the related risk factors including obesity, metabolic factors and inflammatory parameters, with emphasis on potential mechanisms underlying these associations.

METHODS

PRISMA guidelines were followed in this review. Systematic searches were performed using the PubMed/Medline, ScienceDirect, Scopus, EMBASE, ProQuest and Google Scholar databases, up to August 2020 for all relevant published papers.

RESULTS

Out of 362 records screened, 34 articles were included in the final analysis. According to the studies reviewed here, ZAG appears to exert a protective effect against NAFLD by enhancing mRNA expression levels of peroxisome proliferator-activated receptor α (PPARα) and PPARγ, promoting mRNA expression levels of the lipolysis-related genes, reducing mRNA expression levels of the lipogenesis-related genes, increasing hepatic fatty acid oxidation, ameliorating hepatic steatosis, promoting the activity of brown adipose tissue and the expression of thermogenesis-related genes, modulating energy balance and glucose homeostasis, and elevating plasma levels of healthy adipokines such as adiponectin. ZAG can also be involved in the regulation of inflammatory responses by attenuation of the expression of pro-inflammatory and pro-fibrotic mediators.

CONCLUSION

According to the studies reviewed here, ZAG is suggested to be a promising therapeutic target for NAFLD. However, the favourable effects of ZAG need to be confirmed in prospective cohort studies.

Impact of Sodium Glucose Cotransporter 2 Inhibitors on Nonalcoholic Fatty Liver Disease Complicated by Diabetes Mellitus

Sodium glucose cotransporter 2 (SGLT2), a type of membrane protein highly expressed in the kidney, can regulate plasma glucose through the glomerular filtration process by reabsorption from the kidney. SGLT2 inhibitors, which are newly developed oral antidiabetic drugs, can play a role in liver diseases by inhibiting SGLT2-mediated renal glucose reabsorption and inducing glycosuria. Nonalcoholic fatty liver disease (NAFLD) is the most common type of liver disease, resulting in severe liver dysfunction. During the progression of NAFLD, there are some hallmark complications, including lipid metabolism disorders, inflammation induction, and hepatocyte death. Herein, we review several SGLT2 inhibitors that are capable of protecting individuals with NAFLD from severe complications by inhibiting de novo lipogenesis, oxidative responses, inflammation induction, and hepatocyte death.

The impact of sodium glucose co-transporter 2 inhibitors on non-alcoholic fatty liver disease

Affecting one fourth of the global population, non-alcoholic fatty liver disease (NAFLD) is the commonest chronic liver disorder. It encompasses the simple liver fat accumulation to more progressive steatosis, inflammation, and fibrosis characterized as non-alcoholic steatohepatitis (NASH) and in some cases cirrhosis and hepatocellular carcinoma. NAFLD regularly coexists with metabolic disorders, such as obesity and mostly type 2 diabetes mellitus (T2DM). A relatively new class of antidiabetic drugs, the sodium glucose co-transporter 2 (SGLT2) inhibitors exert their action by increasing the urinary glucose and calorie excretion leading to ameliorated plasma glucose levels and lower bodyweight. Recently, several animal studies and human clinical trial have emphasized the possible beneficial impact of SGLT2 inhibitors on NAFLD and its progression to NASH. In this present review, we summarize the current literature regarding the efficacy of the aforementioned category of drugs on anthropometric, laboratory, and histological features of patients with NAFLD. Conclusively, as SGLT2 inhibitors seem to be an appealing therapeutic opportunity for NAFLD management, we identify the open issues and questions to be addressed in order to clarify the impact in choosing antidiabetic medication to treat NAFLD patients associated with T2DM.

Meta-analysis of the effects of sodium glucose cotransporter 2 inhibitors in non-alcoholic fatty liver disease patients with type 2 diabetes

Background and Aim

Sodium glucose cotransporter 2 inhibitors (SGLT‐2i), by way of their unique mode of action, present an attractive strategy for the treatment of type 2 diabetes and non‐alcoholic fatty liver disease (NAFLD), which often coexist and may lead to severe complications. However, the evidence for treatment with SGLT‐2i is limited to small heterogeneous studies. Therefore, this meta‐analysis was conducted to deduce the effects of SGLT‐2i in NAFLD with type 2 diabetes (T2D).

Methods

A web‐based search identified nine randomized controlled trials from the Cochrane Library, Embase, and PubMed for this meta‐analysis. The Comprehensive Meta‐Analysis Software version 3 was used to calculate the effect size.

Result

The outcomes of interest were analyzed from a pooled population of 11 369 patients—7281 on SGLT‐2i and 4088 in the control arm. SGLT‐2i therapy produced a statistically significant improvement in alanine aminotransferase [standardised mean difference (SDM), −0.21, 95% confidence interval (CI), −0.32 to −0.10, P < 0.01], aspartate aminotransferase (Standardised mean difference (SDM), −0.15, 95% CI, −0.24 to −0.07, P < 0.01), and liver fat as measured by proton density fat fraction (SDM, −0.98, 95% CI, −1.53 to −0.44, P < 0.01) in comparison to standard of care or placebo. In addition, there was a significant reduction in glycosylated hemoglobin (SDM, −0.37, 95% CI, −0.60 to −0.14, P < 0.01) and weight (SDM, −0.58, 95% CI, −0.93 to −0.23, P < 0.01) in the SGLT‐2i arm.

Conclusion

This meta‐analysis provides a convincing signal that SGLT‐2i have a salutary effect on NAFLD in type 2 diabetes (T2D), probably driven by an improvement of glycemia and body weight, which in turn attenuates hepatic inflammation and hepatic fat accumulation.

Canagliflozin extends life span in genetically heterogeneous male but not female mice

Canagliflozin (Cana) is an FDA-approved diabetes drug that protects against cardiovascular and kidney diseases. It also inhibits the sodium glucose transporter 2 by blocking renal reuptake and intestinal absorption of glucose. In the context of the mouse Interventions Testing Program, genetically heterogeneous mice were given chow containing Cana at 180 ppm at 7 months of age until their death. Cana extended median survival of male mice by 14%. Cana also increased by 9% the age for 90th percentile survival, with parallel effects seen at each of 3 test sites. Neither the distribution of inferred cause of death nor incidental pathology findings at end-of-life necropsies were altered by Cana. Moreover, although no life span benefits were seen in female mice, Cana led to lower fasting glucose and improved glucose tolerance in both sexes, diminishing fat mass in females only. Therefore, the life span benefit of Cana is likely to reflect blunting of peak glucose levels, because similar longevity effects are seen in male mice given acarbose, a diabetes drug that blocks glucose surges through a distinct mechanism, i.e., slowing breakdown of carbohydrate in the intestine. Interventions that control daily peak glucose levels deserve attention as possible preventive medicines to protect from a wide range of late-life neoplastic and degenerative diseases.

Effects of sodium-glucose cotransporter 2 inhibitors on non-alcoholic fatty liver disease in patients with type 2 diabetes: A meta-analysis of randomized controlled trials

AIMS/INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is increasingly common in patients with type 2 diabetes mellitus. Currently, some studies have found that sodium-glucose cotransporter 2 (SGLT2) inhibitors, a new hypoglycemic drug, can improve non-alcoholic fatty liver in addition to its hypoglycemic effect. Thus, we undertook a meta-analysis of randomized controlled trials to evaluate the efficacy of SGLT2 inhibitors on the treatment of NAFLD.

MATERIALS AND METHODS

PubMed, Embase and the Cochrane Library were searched for randomized controlled trials of SGLT2 inhibitors in patients with NAFLD and type 2 diabetes mellitus up to 1 October 2019. Differences were expressed as weight mean difference (WMD) with 95% confidence interval (CI) for continuous outcomes. The I2 statistic was applied to evaluate the heterogeneity of studies.

RESULTS

A total of six trials including 309 patients were selected into our meta-analysis. SGLT2 inhibitors could reduce alanine aminotransferase (WMD -11.05 IU/L, 95% CI -19.85, -2.25, P = 0.01) and magnetic resonance imaging proton density fat fraction (WMD -2.07%, 95% CI -3.86, -0.28, P = 0.02). However, SGLT2 inhibitors did not reduce aspartate aminotransferase (WMD -1.11 IU/L, 95% CI -2.39, 0.17, P = 0.09). In addition, secondary outcomes, such as bodyweight and visceral fat area, were also reduced (WMD -1.62 kg, 95% CI -2.02, -1.23, P < 0.00001; WMD -19.98 cm2 , 95% CI -27.18, -12.79, P < 0.00001, respectively).

CONCLUSIONS

SGLT2 inhibitors can significantly decrease alanine aminotransferase and liver fat, accompanied with weight loss, which might have a positive effect on fatty liver in patients with type 2 diabetes mellitus. The limitation is that the sample size of the studies was small. Therefore, more large randomized controlled trials specified on NAFLD are required to evaluate these results.

Anti-inflammatory effects of sodium-glucose co-transporter 2 inhibitors on atherosclerosis

Atherosclerosis is a very common macrovascular complication in type 2 diabetes mellitus, and cardiovascular disease is the primary cause of death in diabetes patients. Sodium-glucose cotransporter 2 inhibitors (SGLT-2i) are a newly identified class of drugs targeting the renal proximal tubules to increase glucose excretion. Large-scale clinical trials have confirmed the cardiovascular protective effects of SGLT inhibitors in patients with diabetes diagnosed with or at a higher risk of atherosclerotic cardiovascular disease. In addition to its direct effect on glycemic control, the function of SGLT-2i in the alleviation of volume load, renal protection, and reduction of inflammation plays an essential role in its therapeutic effect on atherosclerosis. SGLT-2i are known to decrease the levels of inflammatory factors in circulation and in arteries in situ, inhibit foam cell formation and macrophage infiltration, and sustain plaque stability, ultimately blocking the development and progression of atherosclerosis.

Association between circulating zinc-α2-glycoprotein levels and the different phenotypes of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) diagnosis combines various clinical phenotypes. The definition of PCOS is still controversial because insulin resistance (IR) and dysmetabolism do not constitute PCOS diagnostic criteria. We analyzed whether a circulating biomarker zinc-α2-glycoprotein (ZAG) related to IR and metabolic dysfunction can predict PCOS phenotypes. We then recruited 100 PCOS patients and 99 healthy women as the control group to assess the relationship between ZAG and metabolic characteristics. The euglycemic-hyperinsulinemic clamp helped assess insulin sensitivity, and the enzyme immunometric assay was deployed for ZAG levels. Our PCOS cohort presented sixty-nine patients with hyperandrogenism, eighty-six patients with chronic oligoanovulation, and eighty-one patients with polycystic ovaries by ultrasonographic evaluation. Additionally, the circulating ZAG levels were considerably reduced in all PCOS patients compared with healthy women (p < 0.05 or p < 0.01). Additionally, sixty-nine PCOS patients had IR, and circulating ZAG levels were also different among the phenotypes. Furthermore, the normoandrogenic type specifically exhibited the highest circulating ZAG levels among all PCOS phenotypes (p < 0.05 or p < 0.01). Additionally, normoandrogenic phenotype patients had reduced HOMA-IR scores and greater M-values than those in the classic phenotypes (p < 0.05). The circulating ZAG levels, however, were not associated with oligoanovulation but were correlated with hyperandrogenism and PCO morphology. In summary, circulating ZAG levels serve as suitable PCOS phenotype biomarkers, aiding physicians to identify women who merit screening.

Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of the metabolic syndrome (MetS) and comprises one of the largest health threats of the twenty-first century. In this chapter, we review the current state of knowledge of NAFLD and underline the striking similarities with atherosclerosis. We first describe current epidemiological data showing the staggering increase of NAFLD numbers and its related clinical and economic costs. We then provide an overview of pathophysiological hepatic processes in NAFLD and highlight the systemic aspects of NAFLD that point toward metabolic crosstalk between organs as an important cause of metabolic disease. Finally, we end by highlighting the currently investigated therapeutic approaches for NAFLD, which also show strong similarities with a range of treatment options for atherosclerosis.

Rise of sodium-glucose cotransporter 2 inhibitors in the management of nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in the Western world. It is more prevalent in male gender, and with increasing age, obesity, and insulin resistance. Besides weight loss, there are limited treatment options. The use of anti-diabetic medications has been studied with mixed results. In this review, we discuss the use of anti-diabetic medications in the management of NAFLD with a specific focus on sodium-glucose cotransporter 2 inhibitors. We shed light on the evidence supporting their use in detail and discuss limitations and future directions.

Serum levels of the adipokine zinc-alpha2-glycoprotein (ZAG) predict mortality in hemodialysis patients

Wasting has been associated with increased cardiovascular and all-cause mortality in chronic kidney disease (CKD). We investigated whether serum zinc-alpha2-glycoprotein (ZAG), a potent cachectic and lipid-mobilizing factor that is increased in patients with CKD, predicts clinical outcomes in patients on chronic hemodialysis. We quantified serum ZAG at baseline in a prospective cohort of 252 patients undergoing maintenance hemodialysis. Serum ZAG concentrations were inversely associated with serum albumin, creatinine, and triglycerides and, conversely, positively associated with age. Although ZAG is strongly linked to protein energy wasting (PEW) in patients with cancer, higher ZAG concentrations were not associated with PEW in our cohort. During a mean study follow-up of 954 days, 49 patients died and 62 patients experienced a cardiovascular event. Kaplan-Meier analysis revealed a significant correlation between serum ZAG concentrations and all-cause mortality and cardiovascular events. In separate multivariable Cox regression models, serum ZAG concentrations remained significantly associated with all-cause mortality and cardiovascular events after adjustment for demographic factors (age, sex, and dialysis vintage), metabolic parameters (serum albumin, prealbumin, triglycerides, cholesterol, normalized protein catabolic rate, and body mass index), and cardiovascular risk factors (diabetes, dyslipidemia, history of cardiovascular disease, smoking, and diuretic use as a proxy of residual renal function). Thus, serum ZAG appears to be a strong and independent predictor of mortality and cardiovascular events in patients with end-stage renal disease. Further studies are necessary to confirm this association and to elucidate the underlying mechanisms.

Vascular Inflammation and Oxidative Stress: Major Triggers for Cardiovascular Disease

Cardiovascular disease is a leading cause of death and reduced quality of life, proven by the latest data of the Global Burden of Disease Study, and is only gaining in prevalence worldwide. Clinical trials have identified chronic inflammatory disorders as cardiovascular risks, and recent research has revealed a contribution by various inflammatory cells to vascular oxidative stress. Atherosclerosis and cardiovascular disease are closely associated with inflammation, probably due to the close interaction of inflammation with oxidative stress. Classical therapies for inflammatory disorders have demonstrated protective effects in various models of cardiovascular disease; especially established drugs with pleiotropic immunomodulatory properties have proven beneficial cardiovascular effects; normalization of oxidative stress seems to be a common feature of these therapies. The close link between inflammation and redox balance was also supported by reports on aggravated inflammatory phenotype in the absence of antioxidant defense proteins (e.g., superoxide dismutases, heme oxygenase-1, and glutathione peroxidases) or overexpression of reactive oxygen species producing enzymes (e.g., NADPH oxidases). The value of immunomodulation for the treatment of cardiovascular disease was recently supported by large-scale clinical trials demonstrating reduced cardiovascular mortality in patients with established atherosclerotic disease when treated by highly specific anti-inflammatory therapies (e.g., using monoclonal antibodies against cytokines). Modern antidiabetic cardiovascular drugs (e.g., SGLT2 inhibitors, DPP-4 inhibitors, and GLP-1 analogs) seem to share these immunomodulatory properties and display potent antioxidant effects, all of which may explain their successful lowering of cardiovascular risk.

Metabolic Targets in Nonalcoholic Fatty Liver Disease

The prevalence and diagnosis of nonalcoholic fatty liver disease (NAFLD) is on the rise worldwide and currently has no FDA-approved pharmacotherapy. The increase in disease burden of NAFLD and a more severe form of this progressive liver disease, nonalcoholic steatohepatitis (NASH), largely mirrors the increase in obesity and type 2 diabetes (T2D) and reflects the hepatic manifestation of an altered metabolic state. Indeed, metabolic syndrome, defined as a constellation of obesity, insulin resistance, hyperglycemia, dyslipidemia and hypertension, is the major risk factor predisposing the NAFLD and NASH. There are multiple potential pharmacologic strategies to rebalance aspects of disordered metabolism in NAFLD. These include therapies aimed at reducing hepatic steatosis by directly modulating lipid metabolism within the liver, inhibiting fructose metabolism, altering delivery of free fatty acids from the adipose to the liver by targeting insulin resistance and/or adipose metabolism, modulating glycemia, and altering pleiotropic metabolic pathways simultaneously. Emerging data from human genetics also supports a role for metabolic drivers in NAFLD and risk for progression to NASH. In this review, we highlight the prominent metabolic drivers of NAFLD pathogenesis and discuss the major metabolic targets of NASH pharmacotherapy.

Sodium-Glucose Cotransporter-2 (SGLT2) Inhibitors: A Clinician's Guide

This comprehensive review covers the historical background, physiology, application in type 2 diabetes, novel uses, cardiovascular benefits, side effects and contraindications of sodium-glucose cotransporter-2 (SGLT2) inhibitors. SGLT2 inhibitors are an insulin-independent class of oral antihyperglycemic medication that clinicians use in the treatment of type 2 diabetes. Multiple landmark clinical trials support the effectiveness of SGLT2 inhibitors in reducing blood glucose levels, but it is important to understand when to properly utilize them. SGLT2 inhibitors are the most beneficial as an adjunct medication in addition to metformin in patients with a history of cardiovascular or renal disease who need further hemoglobin A1c reduction. The novel mechanism of action also demands clinicians be aware of the side effects not typically experienced with other oral antihyperglycemic drugs, such as genital tract infections, lower leg amputations, electrolyte disturbances and bone fractures. On top of their benefits in type 2 diabetes, novel uses for SGLT2 inhibitors are being uncovered. Diabetic patients with non-alcoholic fatty liver disease, who are at an increased risk of cirrhosis and hepatocellular carcinoma, experience a clinically significant reduction in serum alanine aminotransferase levels. SGLT2 inhibitors are also effective at lowering body weight in obese individuals and decreasing systolic blood pressure. Dual SGLT1/SGLT2 inhibitors are currently being investigated as possibly the first oral medication for type 1 diabetes.

Plasma Pharmacokinetic Determination of Canagliflozin and Its Metabolites in a Type 2 Diabetic Rat Model by UPLC-MS/MS

Canagliflozin is a novel, orally selective inhibitor of sodium-dependent glucose co-transporter-2 (SGLT2) for the treatment of patients with type 2 diabetes mellitus. In this study, a sensitive and efficient UPLC-MS/MS method for the quantification of canagliflozin and its metabolites in rat plasma was established and applied to pharmacokinetics in a type 2 diabetic rat model. We firstly investigated the pharmacokinetic changes of canagliflozin and its metabolites in type 2 diabetic rats in order to use canagliflozin more safely, reasonably and effectively. We identified three types of O-glucuronide metabolites (M5, M7 and M17), two kinds of oxidation metabolites (M8 and M9) and one oxidation and glucuronide metabolite (M16) using API 5600 triple-TOF-MS/MS. Following liquid–liquid extraction by tert-butyl methyl ether, chromatographic separation of canagliflozin and its metabolites were performed on a Waters XBridge BEH C18 column (100 × 2.1 mm, 2.5 μm) using 0.1% acetonitrile–formic acid (75:15, v/v) as the mobile phase at a flow rate of 0.7 mL/min. Selected ion monitoring transitions of m/z 462.00→191.10, 451.20→153.10, 638.10→191.10 and 478.00→267.00 were chosen to quantify canagliflozin, empagliflozin (IS), O-glucuronide metabolites (M5, M7 and M17), and oxidation metabolites (M9) using an API 5500-triple-MS/MS in the positive electrospray ionization mode. The validation of the method was found to be of sufficient specificity, accuracy and precision. The pathological condition of diabetes could result in altered pharmacokinetic behaviors of canagliflozin and its metabolites. The pharmacokinetic parameters (AUC_0–t, AUC_0–∞, CL_z/F, and V_z/F) of canagliflozin were significantly different between the CTRL and DM group rats (p < 0.05 or p < 0.01), which may subsequently cause different therapeutic effects.