SGLT2 Inhibitors and the Diabetic Kidney

Exploring the anti-cancer potential of SGLT2 inhibitors in breast cancer treatment in pre-clinical and clinical studies

The link between type 2 diabetes mellitus (T2DM) and an increased risk of breast cancer (BC) has prompted the exploration of novel therapeutic strategies targeting shared metabolic pathways. This review focuses on the emerging evidence surrounding the potential anti-cancer effects of sodium-glucose cotransporter-2 (SGLT2) inhibitors in the context of BC. Preclinical studies have demonstrated that various SGLT2 inhibitors, such as canagliflozin, dapagliflozin, ipragliflozin, and empagliflozin, can inhibit the proliferation of BC cells, induce apoptosis, and modulate key cellular signaling pathways. These mechanisms include the activation of AMP-activated protein kinase (AMPK), suppression of mammalian target of rapamycin (mTOR) signaling, and regulation of lipid metabolism and inflammatory mediators. The combination of SGLT2 inhibitors with conventional treatments, including chemotherapy and radiotherapy, as well as targeted therapies like phosphoinositide 3-kinases (PI3K) inhibitors, has shown promising results in enhancing the anti-cancer efficacy and potentially reducing treatment-related toxicities. The identification of specific biomarkers or genetic signatures that predict responsiveness to SGLT2 inhibitor therapy could enable more personalized treatment selection and optimization, particularly for challenging BC subtypes [e, g., triple negative BC (TNBC)]. Ongoing and future clinical trials investigating the use of SGLT2 inhibitors, both as monotherapy and in combination with other agents, will be crucial in elucidating their translational potential and guiding their integration into comprehensive BC care. Overall, SGLT2 inhibitors represent a novel and promising therapeutic approach with the potential to improve clinical outcomes for patients with various subtypes of BC, including the aggressive and chemo-resistant TNBC.

Effects of Sodium-Glucose Cotransporter 2 Inhibitors on Transcription Regulation of AgRP and POMC Genes

Sodium-glucose cotransporter 2 (SGLT2) inhibitors regulate plasma glucose levels in patients with type 2 diabetes mellitus (T2DM) by inhibiting renal glucose reabsorption. This study investigated the impact of empagliflozin (EMPA), an SGLT2 inhibitor, on hypothalamic energy regulation. To directly investigate the role of SGLT2 inhibitors in the hypothalamus, we administered EMPA through intracerebroventricular (i.c.v.) injections into the murine ventricles. After dental cementing the i.c.v. cannula onto the skull, the mice were given 5 days to recover before receiving vehicle or EMPA (50 nM/2 μL) injections. In a high-fat diet (HFD)-induced obesity model, we determined the gene expression levels of agouti-related peptide (AgRP) and pro-opiomelanocortin (POMC) in the hypothalamus. Additionally, we assessed FoxO1 expression, which regulates AgRP and POMC gene transcription in hypothalamic cell lines. We found that EMPA directly influenced the expression of endogenous mRNA of POMC and AgRP, which are critical for energy homeostasis, and modulated their transcription in high-fat diet-induced obese mice. Additionally, EMPA affected the expression of FoxO1, a key transcriptional regulator of glucose homeostasis, thereby regulating the transcriptional activity of POMC and AgRP. These results indicate that EMPA significantly influences hypothalamic energy homeostasis, highlighting its potential as a regulator in obesity and T2DM management.

Urine Albumin-Creatinine Ratio Variability in People With Type 2 Diabetes: Clinical and Research Implications

RATIONALE & OBJECTIVE

Evidence has demonstrated that albuminuria is a key diagnostic and prognostic marker of diabetic chronic kidney disease, but the impact of its day-to-day variability has not been adequately considered. This study quantified within-individual variability of albuminuria in people with type 2 diabetes to inform clinical albuminuria monitoring.

STUDY DESIGN

Descriptive cross-sectional analysis.

SETTING & PARTICIPANTS

People with type 2 diabetes (n=826, 67.1 [IQR, 60.3-72.4] years, 64.9% male) participating in the Progression of Diabetic Complications (PREDICT) cohort study.

EXPOSURE

Four spot urine collections for measurement of urinary albumin-creatinine ratio (UACR) within 4 weeks.

OUTCOME

Variability of UACR.

ANALYTICAL APPROACH

We characterized within-individual variability (coefficient of variation [CV], 95% limits of random variation, intraclass correlation coefficient), developed a calculator displaying probabilities that any observed difference between a pair of UACR values truly exceeded a 30% difference, and estimated the ranges of diagnostic uncertainty to inform a need for additional UACR collections to exclude or confirm albuminuria. Multiple linear regression examined factors influencing UACR variability.

RESULTS

We observed high within-individual variability (CV 48.8%; 95% limits of random variation showed a repeated UACR to be as high/low as 3.78/0.26 times the first). If a single-collection UACR increased from 2 to 5mg/mmol, the probability that UACR actually increased by at least 30% was only 50%, rising to 97% when 2 collections were obtained at each time point. The ranges of diagnostic uncertainty were 2.0-4.0mg/mmol after an initial UACR test, narrowing to 2.4-3.2 and 2.7-2.9mg/mmol for the mean of 2 and 3 collections, respectively. Some factors correlated with higher (female sex; moderately increased albuminuria) or lower (reduced estimated glomerular filtration rate and sodium-glucose cotransporter 2 inhibitor/angiotensin-converting enzyme inhibitor/angiotensin receptor blocker treatment) within-individual UACR variability.

LIMITATIONS

Reliance on the mean of 4 UACR collections as the reference standard for albuminuria.

CONCLUSIONS

UACR demonstrates a high degree of within-individual variability among individuals with type 2 diabetes. Multiple urine collections for UACR may improve capacity to monitor changes over time in clinical and research settings but may not be necessary for the diagnosis of albuminuria.

PLAIN-LANGUAGE SUMMARY

Albuminuria (albumin in urine) is a diagnostic and prognostic marker of diabetic chronic kidney disease. However, albuminuria can vary within an individual from day to day. We compared 4 random spot urinary albumin-creatinine ratio (UACR) samples from 826 participants. We found that a second UACR collection may be as small as a fourth or as large as almost 4 times the first sample's UACR level. This high degree of variability presents a challenge to our ability to interpret changes in albuminuria. Multiple collections have been suggested as a solution. We have constructed tools that may aid clinicians in deciding how many urine collections are required to monitor and diagnose albuminuria. Multiple urine collections may be required for individual monitoring but not necessarily for diagnosis.

Clinical characteristics and treatment compounds of obesity-related kidney injury

Disorders in energy homeostasis can lead to various metabolic diseases, particularly obesity. The obesity epidemic has led to an increased incidence of obesity-related nephropathy (ORN), a distinct entity characterized by proteinuria, glomerulomegaly, progressive glomerulosclerosis, and renal function decline. Obesity and its associated renal damage are common in clinical practice, and their incidence is increasing and attracting great attention. There is a great need to identify safe and effective therapeutic modalities, and therapeutics using chemical compounds and natural products are receiving increasing attention. However, the summary is lacking about the specific effects and mechanisms of action of compounds in the treatment of ORN. In this review, we summarize the important clinical features and compound treatment strategies for obesity and obesity-induced kidney injury. We also summarize the pathologic and clinical features of ORN as well as its pathogenesis and potential therapeutics targeting renal inflammation, oxidative stress, insulin resistance, fibrosis, kidney lipid accumulation, and dysregulated autophagy. In addition, detailed information on natural and synthetic compounds used for the treatment of obesity-related kidney disease is summarized. The synthesis of detailed information aims to contribute to a deeper understanding of the clinical treatment modalities for obesity-related kidney diseases, fostering the anticipation of novel insights in this domain.

The antidiabetic drug ipragliflozin induces vasorelaxation of rabbit femoral artery by activating a Kv channel, the SERCA pump, and the PKA signaling pathway

We explored the vasorelaxant effects of ipragliflozin, a sodium-glucose cotransporter-2 inhibitor, on rabbit femoral arterial rings. Ipragliflozin relaxed phenylephrine-induced pre-contracted rings in a dose-dependent manner. Pre-treatment with the ATP-sensitive K+ channel inhibitor glibenclamide (10 μM), the inwardly rectifying K+ channel inhibitor Ba2+ (50 μM), or the Ca2+-sensitive K+ channel inhibitor paxilline (10 μM) did not influence the vasorelaxant effect. However, the voltage-dependent K+ (Kv) channel inhibitor 4-aminopyridine (3 mM) reduced the vasorelaxant effect. Specifically, the vasorelaxant response to ipragliflozin was significantly attenuated by pretreatment with the Kv7.X channel inhibitors linopirdine (10 μM) and XE991 (10 μM), the sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) pump inhibitors thapsigargin (1 μM) and cyclopiazonic acid (10 μM), and the cAMP/protein kinase A (PKA)-associated signaling pathway inhibitors SQ22536 (50 μM) and KT5720 (1 μM). Neither the cGMP/protein kinase G (PKG)-associated signaling pathway nor the endothelium was involved in ipragliflozin-induced vasorelaxation. We conclude that ipragliflozin induced vasorelaxation of rabbit femoral arteries by activating Kv channels (principally the Kv7.X channel), the SERCA pump, and the cAMP/PKA-associated signaling pathway independent of other K+ (ATP-sensitive K+, inwardly rectifying K+, and Ca2+-sensitive K+) channels, cGMP/PKG-associated signaling, and the endothelium.

Diabetes and Renal Complications: An Overview on Pathophysiology, Biomarkers and Therapeutic Interventions

Diabetic kidney disease (DKD) is a major microvascular complication of both type 1 and type 2 diabetes. DKD is characterised by injury to both glomerular and tubular compartments, leading to kidney dysfunction over time. It is one of the most common causes of chronic kidney disease (CKD) and end-stage renal disease (ESRD). Persistent high blood glucose levels can damage the small blood vessels in the kidneys, impairing their ability to filter waste and fluids from the blood effectively. Other factors like high blood pressure (hypertension), genetics, and lifestyle habits can also contribute to the development and progression of DKD. The key features of renal complications of diabetes include morphological and functional alterations to renal glomeruli and tubules leading to mesangial expansion, glomerulosclerosis, homogenous thickening of the glomerular basement membrane (GBM), albuminuria, tubulointerstitial fibrosis and progressive decline in renal function. In advanced stages, DKD may require treatments such as dialysis or kidney transplant to sustain life. Therefore, early detection and proactive management of diabetes and its complications are crucial in preventing DKD and preserving kidney function.

Effect of Sodium-Glucose Cotransporter 2 Inhibitors on the 24-Hour Ambulatory Blood Pressure in Patients With Type 2 Diabetes Mellitus and Hypertension: An Updated Meta-Analysis

OBJECTIVE

Sodium-glucose cotransporter 2 inhibitors (SGLT2i), initially developed for type 2 diabetes mellitus (DM) treatment, have shown potential benefits beyond glycemic control, including a positive impact on the blood pressure (BP). This meta-analysis aimed to evaluate their effects on patients with type 2 DM and hypertension.

METHODS

We searched the PubMed, Google Scholar, and Cochrane databases for relevant randomized controlled trials published until May 31, 2023. Ten randomized controlled trials involving participants with confirmed type 2 DM were selected. The intervention group received SGLT2i, whereas the control group received a placebo or standard care. The primary outcomes were the 24-hour ambulatory systolic BP (SBP) and diastolic BP (DBP).

RESULTS

The results showed a significant reduction in the 24-hour ambulatory SBP (weighted mean difference, -5.08 mm Hg; 95% confidence interval, -7.02 to -3.14; P <.00001) and DBP (weighted mean difference, -2.73 mm Hg; 95% confidence interval, -4.25 to -1.20; P =.0005) with the use of SGLT2i compared with that using the placebo. However, a high-heterogeneity level was observed in both analyses (SBP, I2 = 83%; DBP, I2 = 91%). Sensitivity analysis excluding specific studies reduced heterogeneity while maintaining statistically significant and clinically relevant reductions in the BP.

CONCLUSION

In conclusion, this meta-analysis proves that SGLT2i significantly reduce the 24-hour ambulatory BP. SGLT2i may be considered an effective treatment option for lowering the BP in addition to standard care in patients with hypertension and type 2 DM.

SGLT2 Inhibitors in Kidney Diseases-A Narrative Review

Some of the most common conditions affecting people are kidney diseases. Among them, we distinguish chronic kidney disease and acute kidney injury. Both entities pose serious health risks, so new drugs are still being sought to treat and prevent them. In recent years, such a role has begun to be assigned to sodium-glucose cotransporter-2 (SGLT2) inhibitors. They increase the amount of glucose excreted in the urine. For this reason, they are currently used as a first-line drug in type 2 diabetes mellitus. Due to their demonstrated cardioprotective effect, they are also used in heart failure treatment. As for the renal effects of SGLT2 inhibitors, they reduce intraglomerular pressure and decrease albuminuria. This results in a slower decline in glomelular filtration rate (GFR) in patients with kidney disease. In addition, these drugs have anti-inflammatory and antifibrotic effects. In the following article, we review the evidence for the effectiveness of this group of drugs in kidney disease and their nephroprotective effect. Further research is still needed, but meta-analyses indicate SGLT2 inhibitors' efficacy in kidney disease, especially the one caused by diabetes. Development of new drugs and clinical trials on specific patient subgroups will further refine their nephroprotective effects.

Effect of dapagliflozin on collectins and complement activation in plasma from patients with type 2 diabetes and albuminuria: Data from the DapKid cohort

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT- 2) inhibitors exert cardiovascular and kidney-protective effects in people with diabetes. Attenuation of inflammation could be important for systemic protection. The lectin pathway of complement system activation is linked to diabetic nephropathy. We hypothesized that SGLT-2 inhibitors lower the circulating level of pattern-recognition molecules of the lectin cascade and attenuate systemic complement activation.

METHODS

Analysis of paired plasma samples from the DapKid crossover intervention study where patients with type 2 diabetes mellitus (T2DM) and albuminuria were treated with dapagliflozin and placebo for 12 weeks (10 mg/day, n=36). ELISA was used to determine concentrations of collectin kidney 1 (CL-K1), collectin liver 1 (CL-L1), mannose-binding lectin (MBL), MBL-associated serine protease 2 (MASP-2), the anaphylatoxin complement factor 3a (C3a), the stable C3 split product C3dg and the membrane attack complex (sC5b-9).

RESULTS

As published before, dapagliflozin treatment lowered Hba1C from 74 (14.9) mmol/mol to 66 (13.9) mmol/mol (p<0.0001), and the urine albumin/creatinine ratio from 167.8 mg/g to 122.5 mg/g (p<0.0001). Plasma concentrations of CL-K1, CL-L1, MBL, and MASP-2 did not change significantly after dapagliflozin treatment (P>0.05) compared to placebo treatment. The plasma levels of C3a (P<0.05) and C3dg (P<0.01) increased slightly but significantly, 0.6 [0.2] units/mL and 76 [52] units/mL respectively, after dapagliflozin treatment. The C9-associated neoepitope in C5b-9 did not change in plasma concentration by dapagliflozin (P>0.05).

CONCLUSION

In patients with type 2 diabetes and albuminuria, SGLT-2 inhibition resulted in modest C3 activation in plasma, likely not driven by primary changes in circulating collectins and not resulting in changes in membrane attack complex. Based on systemic analyses, organ-specific local protective effects of gliflozins against complement activation cannot be excluded.

Endothelial NOX5 Obliterates the Reno-Protective Effect of Nox4 Deletion by Promoting Renal Fibrosis via Activation of EMT and ROS-Sensitive Pathways in Diabetes

Chronic hyperglycemia induces intrarenal oxidative stress due to the excessive production of reactive oxygen species (ROS), leading to a cascade of events that contribute to the development and progression of diabetic kidney disease (DKD). NOX5, a pro-oxidant NADPH oxidase isoform, has been identified as a significant contributor to renal ROS in humans. Elevated levels of renal ROS contribute to endothelial cell dysfunction and associated inflammation, causing increased endothelial permeability, which can disrupt the renal ecosystem, leading to progressive albuminuria and renal fibrosis in DKD. This study specifically examines the contribution of endothelial cell-specific human NOX5 expression in renal pathology in a transgenic mouse model of DKD. This study additionally compares NOX5 with the previously characterized NADPH oxidase, NOX4, in terms of their relative roles in DKD. Regardless of NOX4 pathway, this study found that endothelial cell-specific expression of NOX5 exacerbates renal injury, albuminuria and fibrosis. This is attributed to the activation of the endothelial mesenchymal transition (EMT) pathway via enhanced ROS formation and the modulation of redox-sensitive factors. These findings underscore the potential therapeutic significance of NOX5 inhibition in human DKD. The study proposes that inhibiting NOX5 could be a promising approach for mitigating the progression of DKD and strengthens the case for the development of NOX5-specific inhibitors as a potential therapeutic intervention.

Identification of risk factors associated with acute kidney injury in patients taking sodium-glucose cotransporter-2 inhibitors

STUDY OBJECTIVE

Studies have demonstrated sodium-glucose cotransporter-2 (SGLT2) inhibitors are kidney protective; however, their ability to cause hemodynamic changes may predispose patients to acute kidney injury (AKI). An FDA warning recommends evaluating for factors that predispose patients to AKI before initiating a SGLT2 inhibitor. The primary objective of this study is to identify risk factors that may predispose persons with diabetes to AKI when initiating SGLT2 inhibitor therapy.

DESIGN

Multicenter retrospective cohort chart review.

DATA SOURCE

Study patients were identified through an electronic medical record generated report if they had type 2 diabetes and were prescribed a SGLT2 inhibitor from January 2013 to September 2019.

PATIENTS

Patients were included if they were receiving care at Advocate Medical Group and were confirmed to have taken one of the four SGLT2 inhibitors available at the time of study approval, canagliflozin, dapagliflozin, empagliflozin, or ertugliflozin, for at least 7 days. Patients were excluded if they did not have a basic metabolic panel or comprehensive metabolic panel recorded 1 year prior to or 6 months after SGLT2 inhibitor therapy initiation.

RESULTS

Data extraction from the electronic medical record identified 6425 patients receiving a SGLT2 inhibitor, of which 1962 met inclusion criteria and were included for analysis. Thirty-five (1.8%) patients experienced an AKI after SGLT2 inhibitor therapy initiation. There was no statistically significant difference between groups based on background medication use (p = 0.325). At baseline, patients experiencing an AKI after SGLT2 inhibitor initiation were more likely to be older in age (p = 0.010), have a higher serum potassium (p < 0.001), blood glucose (p = 0.018), SCr (p = 0.009) and UACR (p < 0.001), and a lower eGFR (p = 0.028) compared to those who did not experience AKI.

CONCLUSIONS

The transient eGFR decline with SGLT2 inhibitor initiation should be expected and is generally not an indication to discontinue therapy. Future initiatives should be directed at increasing knowledge of monitoring recommendations for these agents.

Interactive Effects of Empagliflozin and Hyperglycemia on Urinary Amino Acids in Individuals With Type 1 Diabetes

Optimizing energy use in the kidney is critical for normal kidney function. Here, we investigate the effect of hyperglycemia and sodium-glucose cotransporter 2 (SGLT2) inhibition on urinary amino acid excretion in individuals with type 1 diabetes (T1D). The open-label ATIRMA trial assessed the impact of 8 weeks of 25 mg empagliflozin orally once per day in 40 normotensive normoalbuminuric young adults with T1D. A consecutive 2-day assessment of clamped euglycemia and hyperglycemia was evaluated at baseline and posttreatment visits. Principal component analysis was performed on urinary amino acids grouped into representative metabolic pathways using MetaboAnalyst. At baseline, acute hyperglycemia was associated with changes in 25 of the 33 urinary amino acids or their metabolites. The most significant amino acid metabolites affected by acute hyperglycemia were 3-hydroxykynurenine, serotonin, glycyl-histidine, and nicotinic acid. The changes in amino acid metabolites were reflected by the induction of four biosynthetic pathways: aminoacyl-tRNA; valine, leucine, and isoleucine; arginine; and phenylalanine, tyrosine, and tryptophan. In acute hyperglycemia, empagliflozin significantly attenuated the increases in aminoacyl-tRNA biosynthesis and valine, leucine, and isoleucine biosynthesis. Our findings using amino acid metabolomics indicate that hyperglycemia stimulates biosynthetic pathways in T1D. SGLT2 inhibition may attenuate the increase in biosynthetic pathways to optimize kidney energy metabolism.

ARTICLE HIGHLIGHTS

Sodium-Glucose Co-Transporter 2 Inhibitors: Mechanism of Action and Efficacy in Non-Diabetic Kidney Disease from Bench to Bed-Side

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are currently available for the management of type 2 diabetes mellitus. SGLT2i acts by inhibiting renal SGLT2, thereby increasing glucosuria and lowering serum glucose. Recent trials are emerging supporting a role for SGLT2i irrespective of the diabetic status pointing towards that SGLT2i have other mechanisms of actions beyond blood sugar control. In this review, we will shed light on the role of this group of medications that act as SGLT2i in non-diabetics focusing on pre-clinical and clinical data highlighting the mechanism of renoprotection and effects of SGLT2i in the non-diabetic kidneys.

Ion homeostasis in diabetic kidney disease

The complications of type 2 diabetes are a major global public health problem with high incidence and mortality, affecting almost all individuals with diabetes worldwide. Diabetic kidney disease (DKD) is one such primary complication and has become a leading cause of end-stage renal disease in patients with diabetes. Progression from diabetes to DKD is a complex process typically involving multiple mechanisms. Recent remarkable clinical benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors in diabetes and DKD highlight the critical impact of renal ion homeostasis on disease progression. This review comprehensively examines the impact of ion homeostasis on the transition from diabetes to DKD, outlining possible therapeutic interventions and addressing the ongoing challenges in this rapidly developing field.

Effects of total flavones of Abelmoschus manihot (L.) on the treatment of diabetic nephropathy via the activation of solute carriers in renal tubular epithelial cells

As a traditional Chinese medicine, Huangkui capsule (HKC) has been used to treat patients with kidney diseases, including diabetic nephropathy (DN). We have recently demonstrated that HKC could re-regulate the activities of solute carriers (SLC)s in proximal and distal convoluted tubules of kidneys in regression of the development of DN. The main active chemical constituents of HKC are the flavones of Abelmoschus manihot (L.). The current study aims to further evaluate the efficacy of total flavones of A. manihot (TFA) in the regression of DN by analyzing SLC activities in proximal and distal convoluted tubules of kidneys. TFA (0.076 g/kg/d) or vehicle was administered in db/db mice, the animal model of type 2 diabetes and DN, daily via oral gavage for four weeks. Blood glucose levels and urinary albumin-to-creatinine ratio (UACR) were measured and used for the determination of T2D and DN. Ten SLCs, including slc2a2, slc4A1, slc5a2, slc5A3, slc5a8, slc6a20, slc27a2, slc12a3, slc34a1 and slc38a2 were highly expressed in proximal and distinct convoluted tubules of kidneys. Their expression at mRNA and protein levels before and after TFA treatment were analyzed with real-time RT-PCR and immunohistochemistry. Data showed that UACR in the db/db mice after TFA treatment was significantly decreased. Compared with the group of non-diabetic control, slc2a2, slc4A1, slc5a2, slc5A3, slc5a8, slc6a20, slc27a2, slc12a3, slc34a1 and slc38a2 in the group of DN were down-regulated but up-regulated after TFA treatment. Further analyses of whole kidney sections indicated that the numbers and structures of the nephron in db/db mice was increased and improved after TFA treatment. Thereby, the current study provides further evidence that the flavones in A. manihot have pharmacological effects on the treatment of DN by improving the biological function of SLCs in kidneys.

Trajectories of eGFR and risk of albuminuria in youth with type 2 diabetes: results from the TODAY cohort study

BACKGROUND

We conducted exploratory analyses to identify distinct trajectories of estimated glomerular filtration rate (eGFR) and their relationship with hyperfiltration, subsequent rapid eGFR decline, and albuminuria in participants with youth-onset type 2 diabetes enrolled in the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study.

METHODS

Annual serum creatinine, cystatin C, urine albumin, and creatinine measurements were obtained from 377 participants followed for ≥ 10 years. Albuminuria and eGFR were calculated. Hyperfiltration peak is the greatest eGFR inflection point during follow-up. Latent class modeling was applied to identify distinct eGFR trajectories.

RESULTS

At baseline, participants' mean age was 14 years, type 2 diabetes duration was 6 months, mean HbA1c was 6%, and mean eGFR was 120 ml/min/1.73 m2. Five eGFR trajectories associated with different rates of albuminuria were identified, including a "progressive increasing eGFR" group (10%), three "stable eGFR" groups with varying starting mean eGFR, and an "eGFR steady decline" group (1%). Participants who exhibited the greatest peak eGFR also had the highest levels of elevated albuminuria at year 10. This group membership was characterized by a greater proportion of female and Hispanic participants.

CONCLUSIONS

Distinct eGFR trajectories that associate with albuminuria risk were identified, with the eGFR trajectory characterized by increasing eGFR over time associating with the highest level of albuminuria. These descriptive data support the current recommendations to estimate GFR annually in young persons with type 2 diabetes and provide insight into eGFR-related factors which may contribute to predictive risk strategies for kidney disease therapies in youth with type 2 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00081328, date registered 2002. A higher resolution version of the Graphical abstract is available as Supplementary information.

Evaluation of Loop Diuretic Dosing Following Sodium-Glucose Cotransporter 2 Inhibitor Initiation in Patients With Heart Failure

Introduction: Sodium-glucose cotransporter 2 inhibitors (SGLT2is) have demonstrated cardiovascular benefits in patients with heart failure, many of which take loop diuretics. There are no evidence-based recommendations identifying which patients may require loop diuretic dose decreases or how to adjust loop diuretic doses when SGLT2is are initiated. Objectives: The main objective of this study was to investigate the frequency and degree of adjustments in loop diuretic doses after SGLT2i initiation in patients with heart failure. Methods: In this retrospective evaluation, patients seen in the UCHealth system with a diagnosis of heart failure who were prescribed a loop diuretic before initiation of SGLT2i were identified. We described loop diuretic dose changes at the time of SGLT2i initiation, at 6 months after initiation, and at 1 year after initiation. We also described de-escalation of maintenance medications that can contribute to hypotension at these time points. Data were evaluated using descriptive statistics. Results: A total of 100 patients were included. Loop diuretic dose was reduced empirically upon SGLT2i initiation in 2.0% of patients. Reduction of loop diuretic dose within the first 6 months of starting an SGLT2i occurred in 8.0% of patients. From baseline to 12 months after starting SGLT2i therapy, 14.0% of patients had loop diuretic dose reduction. Conclusions: Most of our patients with HF did not have change in loop diuretic dose after initiation of an SGLT2i. In patients who did have loop diuretic dose reduction, most occurred within 6 months after starting SGLT2i therapy rather than empirically at time of initiation.

ELABELA protects against diabetic kidney disease by activating high glucose-inhibited renal tubular autophagy

ELABELA (ELA), an endogenous ligand of the apelin receptor (also known as apelin peptide jejunum [APJ]), has been shown to decrease in the plasma of patients with diabetic kidney disease (DKD). In the current study, we explored the potential function as well as the underlying mechanisms of ELA in DKD. We first found that the ELA levels were decreased in the kidneys of DKD mice. Then, we found that ELA administration mitigated renal damage and downregulated the expression of fibronectin, collagen Ⅳ, and transforming growth factor-β1 in the db/db mice and the high glucose cultured HK-2 cells. Furthermore, the autophagy markers, Beclin-1 and LC3-Ⅱ/LC3-Ⅰ ratio, were significantly impaired in DKD, but the ELA treatment reversed these alterations. Mechanistically, the inhibitory effects of ELA on the secretion of fibrosis-associated proteins in high glucose conditions were blocked by pretreatment with 3-methyladenine (an autophagy inhibitor). In summary, these in vivo and in vitro results demonstrate that ELA effectively protects against DKD by activating high glucose-inhibited renal tubular autophagy, potentially serving as a novel therapeutic candidate for DKD.

Nicotinamide Adenine Dinucleotide in Aging Biology: Potential Applications and Many Unknowns

Recent research has unveiled an expansive role of NAD+ in cellular energy generation, redox reactions, and as a substrate or cosubstrate in signaling pathways that regulate health span and aging. This review provides a critical appraisal of the clinical pharmacology and the preclinical and clinical evidence for therapeutic effects of NAD+ precursors for age-related conditions, with a particular focus on cardiometabolic disorders, and discusses gaps in current knowledge. NAD+ levels decrease throughout life; age-related decline in NAD+ bioavailability has been postulated to be a contributor to many age-related diseases. Raising NAD+ levels in model organisms by administration of NAD+ precursors improves glucose and lipid metabolism; attenuates diet-induced weight gain, diabetes, diabetic kidney disease, and hepatic steatosis; reduces endothelial dysfunction; protects heart from ischemic injury; improves left ventricular function in models of heart failure; attenuates cerebrovascular and neurodegenerative disorders; and increases health span. Early human studies show that NAD+ levels can be raised safely in blood and some tissues by oral NAD+ precursors and suggest benefit in preventing nonmelanotic skin cancer, modestly reducing blood pressure and improving lipid profile in older adults with obesity or overweight; preventing kidney injury in at-risk patients; and suppressing inflammation in Parkinson disease and SARS-CoV-2 infection. Clinical pharmacology, metabolism, and therapeutic mechanisms of NAD+ precursors remain incompletely understood. We suggest that these early findings provide the rationale for adequately powered randomized trials to evaluate the efficacy of NAD+ augmentation as a therapeutic strategy to prevent and treat metabolic disorders and age-related conditions.

[Evolution of the non-insulin therapeutic strategy in type 2 diabetes]

While the prevalence of diabetes continues to rise worldwide, with 537 million adults aged 20-79-years-old having diabetes in 2021, the development of new therapeutic classes improving not only glycemic control but also kidney function and cardiovascular prevention has revolutionized patient care. Today, the treatment of diabetes is no longer just the treatment of blood sugar level. In this context, the individualized therapeutic strategy has been completely reviewed, with in particular sulfamides indicated much later in the therapeutic strategy, while SGLT2 inhibitors are indicated very early in patients with kidney disease and/or with ischemic heart disease or chronic heart failure, and GLP-1 analogues in obese patients and/or in primary or secondary cardiovascular prevention. As for lifestyle rules and metformin, they remain the cornerstone of treatment. Knowledge of antidiabetic effects in terms of efficacy and hypoglycemic risk, of cardiovascular, nephroprotective and weight effects is essential to optimize the management of diabetic patients today.

Reno- and cardioprotective molecular mechanisms of SGLT2 inhibitors beyond glycemic control: from bedside to bench

Large placebo-controlled clinical trials have shown that sodium-glucose cotransporter-2 inhibitors (SGLT2i) delay the deterioration of renal function and reduce cardiovascular events in a glucose-independent manner, thereby ultimately reducing mortality in patients with chronic kidney disease (CKD) and/or heart failure. These existing clinical data stimulated preclinical studies aiming to understand the observed clinical effects. In animal models, it was shown that the beneficial effect of SGLT2i on the tubuloglomerular feedback (TGF) improves glomerular pressure and reduces tubular workload by improving renal hemodynamics, which appears to be dependent on salt intake. High salt intake might blunt the SGLT2i effects on the TGF. Beyond the salt-dependent effects of SGLT2i on renal hemodynamics, SGLT2i inhibited several key aspects of macrophage-mediated renal inflammation and fibrosis, including inhibiting the differentiation of monocytes to macrophages, promoting the polarization of macrophages from a proinflammatory M1 phenotype to an anti-inflammatory M2 phenotype, and suppressing the activation of inflammasomes and major proinflammatory factors. As macrophages are also important cells mediating atherosclerosis and myocardial remodeling after injury, the inhibitory effects of SGLT2i on macrophage differentiation and inflammatory responses may also play a role in stabilizing atherosclerotic plaques and ameliorating myocardial inflammation and fibrosis. Recent studies suggest that SGLT2i may also act directly on the Na+/H+ exchanger and Late-INa in cardiomyocytes thus reducing Na+ and Ca2+ overload-mediated myocardial damage. In addition, the renal-cardioprotective mechanisms of SGLT2i include systemic effects on the sympathetic nervous system, blood volume, salt excretion, and energy metabolism.

Redox regulation in diabetic kidney disease

Diabetic kidney disease (DKD) is one of the most devastating complications of diabetes mellitus, where currently there is no cure available. Several important mechanisms contribute to the pathogenesis of this complication, with oxidative stress being one of the key factors. The past decades have seen a large number of publications with various aspects of this topic; however, the specific details of redox regulation in DKD are still unclear. This is partly because redox biology is very complex, coupled with a complex and heterogeneous organ with numerous cell types. Furthermore, often times terms such as "oxidative stress" or reactive oxygen species are used as a general term to cover a wide and rich variety of reactive species and their differing reactions. However, no reactive species are the same, and not all of them are capable of biologically relevant reactions or "redox signaling." The goal of this review is to provide a biochemical background for an array of specific reactive oxygen species types with varying reactivity and specificity in the kidney as well as highlight some of the advances in redox biology that are paving the way to a better understanding of DKD development and risk.

Evaluation of the efficacy of Abelmoschus manihot (L.) on diabetic nephropathy by analyzing biomarkers in the glomeruli and proximal and distal convoluted tubules of the kidneys

Introduction: As a traditional Chinese medicine, Abelmoschus manihot (L.) in the form of Huangkui (HK) capsule has been used as a medication for kidney diseases, including diabetic nephropathy (DN), in China. The most significant effect of HK capsule treatment in kidney diseases is the reduction of albuminuria and proteinuria. To evaluate the efficacy of HK capsule in the regression of DN, in the current study, we analyzed the biomarkers in the glomerulus and proximal and distal convoluted tubules in the kidneys of db/db mice, the animal model for type 2 diabetes and DN. Methods: Huangkui capsules (0.84 g/kg/d) or vehicle were administered daily via oral gavage for 4 weeks in db/db mice. Urinary albumin-to-creatinine ratio and blood glucose levels were measured during the whole experimental period. Five biomarkers in the glomerulus and proximal and distal convoluted tubules in the kidneys were selected, namely, col4a3, slc5a2, slc34a1, slc12a3, and slc4a1, and their activities at mRNA and protein levels before and after HK capsule treatment were analyzed by real-time RT-PCR and immunohistochemistry. Result and discussion: After HK capsule treatment for 4 weeks, the urinary albumin-to-creatinine ratio in db/db mice was found to be significantly decreased. The activities of col4a3, slc5a2, slc34a1, slc12a3, and slc4a1 in the kidneys were upregulated in db/db mice prior to the treatment but downregulated after HK capsule treatment. Further analyses of the fields of whole kidney tissue sections demonstrated that the number of nephrons in the kidneys of db/db mice with HK capsule treatment was higher than that in the kidneys of db/db mice without HK capsule treatment. Thereby, the current study provides experimental evidence confirming the medical efficacy of A. manihot in the reduction of albuminuria and proteinuria, suggesting that A. manihot may have pharmacological efficacy in the regression of the development of type 2 diabetes-DN.

Management of Hypertension in Fabry Disease

Fabry disease (FD), a rare X-linked lysosomal storage disorder that depletes alpha-galactosidase A (α-GalA), is caused by mutations in the GLA gene. Diminished α-GalA enzyme activity results in the accumulation of Gb3 and lyso-Gb3. The pathophysiology of hypertension in FD is complex and unclear. The storage of Gb3 in arterial endothelial cells and smooth muscle cells is known to produce vascular injury by increasing oxidative stress and inflammatory cytokines as a primary pathophysiological mechanism. In addition, Fabry nephropathy developed, resulting in a decrease in kidney function and contributing to hypertension. The prevalence of hypertension in patients with FD was between 28.4% and 56%, whereas hypertension in patients with chronic kidney disease ranged between 33% and 79%. A study using 24-hour ambulatory blood pressure monitoring (ABPM) to measure blood pressure (BP) indicated a high prevalence of uncontrolled hypertension in FD. Thus, 24-hour ABPM ought to be considered for FD hypertension assessments. Appropriate treatment of hypertension is believed to reduce mortality in patients with FD caused by kidney disease, cardiovascular disease, and cerebrovascular disease because hypertension significantly impacts organ damage. Up to 70% of FD patients have been reported to have kidney involvement, and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers prescribed for proteinuria are recommended as first-line therapy with antihypertensive drugs. In conclusion, hypertension should be controlled appropriately, given the different morbidity and mortality caused by significant organ involvement in FD patients.

Separate and combined effects of semaglutide and empagliflozin on kidney oxygenation and perfusion in people with type 2 diabetes: a randomised trial

AIMS/HYPOTHESIS

Glucagon-like peptide-1 receptor agonists (GLP-1ras) and sodium-glucose cotransporter 2 inhibitors (SGLT2is) have shown kidney-protective effects. Improved kidney oxygenation and haemodynamic changes are suggested mechanisms; however, human data are scarce. We therefore investigated whether semaglutide (GLP-1ra), empagliflozin (SGLT2i) or their combination improve kidney oxygenation and perfusion.

METHODS

The trial was undertaken at Aarhus University Hospital, Denmark. A total of 120 people with type 2 diabetes (HbA1c ≥48 mmol/mol [6.5%]) and at high risk of CVD (age ≥50 years) were randomised into four parallel groups (n=30 in each group) for 32 weeks: 1.0 mg semaglutide (open label); 10 mg empagliflozin (blinded to participants, caregivers, examiners and outcome assessors); their combination (1.0 mg semaglutide open label plus 10 mg empagliflozin blinded to participants, caregivers, examiners and outcome assessors); and placebo tablet (blinded to participants, caregivers, examiners and outcome assessors). Sequentially numbered, sealed envelopes containing computer-generated randomisation codes, provided by Glostrup Pharmacy, Glostrup, Denmark, determined the intervention. The two co-primary outcomes were change in kidney oxygenation and change in arterial stiffness. This paper reports on kidney oxygenation, for which 80 individuals as prespecified, 20 in each group, underwent MRI. We primarily hypothesised that kidney oxygenation would be improved in the active treatment groups compared with placebo after 32 weeks. Secondary outcomes included changes in kidney perfusion, erythropoietin, haematocrit, urine albumin/creatinine ratio (UACR) and GFR (measured using technetium-99m) compared with baseline and between treatment groups at week 32.

RESULTS

Our model estimated a common baseline R2* value across all four groups in the cortex and the medulla. At baseline, the value was 24.5 (95% CI 23.9, 24.9) Hz in the medulla. After 32 weeks, the R2* values in the medulla were estimated to be 25.4 (95% CI 24.7, 26.2) Hz in the empagliflozin group and 24.5 (95% CI 23.9, 25.1) Hz in the placebo group (p=0.016) (higher R2* corresponds to a lower oxygenation). Semaglutide decreased perfusion in both the cortex and the medulla. Empagliflozin increased erythropoietin and haematocrit. All three active treatments decreased GFR but not UACR. Ten serious adverse events were reported, among them two occurrences of semaglutide-associated obstipation.

CONCLUSIONS/INTERPRETATION

Our hypothesis, that semaglutide, empagliflozin or their combination improve kidney oxygenation, was rejected. On the contrary, empagliflozin induced a reduction in medullary kidney oxygenation. Semaglutide substantially reduced kidney perfusion without affecting oxygenation.

TRIAL REGISTRATION

Clinicaltrialsregister.eu EudraCT 2019-000781-38 FUNDING: Novo Nordisk Foundation, Central Denmark Region Research Fund and Danish Medical Associations Research Foundation.

Exposure-Response Analysis of the Sodium-Glucose Cotransporter-2 Inhibitors Dapagliflozin and Empagliflozin on Kidney Hemodynamics in Patients with Type 2 Diabetes

Sodium-glucose cotransporter-2 (SGLT2) inhibitors improve markers for renal and cardiovascular outcomes in patients with and without type 2 diabetes (T2D). To assess whether individual differences in plasma drug exposure can explain inter-individual response variation, we characterized the exposure-response relationship for two SGLT2 inhibitors on several clinical and kidney hemodynamic variables. Data were obtained from two studies, RED and RECOLAR, assessing the effects of once-daily 10 mg dapagliflozin or empagliflozin, respectively, on kidney hemodynamics in patients with T2D. Individual plasma exposure was estimated using non-compartmental analyses and exposure-response relationships were assessed using linear mixed-effects models. In 23 patients participating in RED, the dapagliflozin geometric mean apparent area under the concentration-time curve during one dosing interval at steady state (AUC_0-tau,ss) was 1153.1 µg/L*h (coefficient of variation (CV) 81.8%) and associated, per doubling, with decreases in body weight (0.29 kg, p < 0.001), systolic blood pressure (0.80 mmHg, p = 0.002), measured glomerular filtration rate (mGFR) (0.83 mL/min, p = 0.03), and filtration fraction (0.09%, p = 0.04). In 20 patients participating in RECOLOR, the empagliflozin geometric mean AUC_0-tau,ss was 2035.7 nmol/L*h (CV 48.4%) and associated, per doubling, with decreases in body weight (0.13 kg, p = 0.002), systolic blood pressure (0.65 mmHg, p = 0.045), and mGFR (0.78 mL/min, p = 0.002). To conclude, dapagliflozin and empagliflozin plasma exposure was highly variable between patients and associated with inter-individual variation in response variables.

Pleiotropic Effects of Sodium-Glucose Cotransporter-2 Inhibitors in Cardiovascular Disease and Chronic Kidney Disease

Sodium-glucose cotransporter-2 inhibitors (SGLT2is) have been shown to improve cardiovascular and renal outcomes in patients with established cardiovascular disease, chronic kidney disease (CKD), and heart failure (HF) with reduced or preserved ejection fraction. Clinical benefit has been substantiated in patients with and without type 2 diabetes (T2D). Consequently, SGLT2is have an increasingly important role in HF and CKD management that extends beyond T2D treatment. Their pleiotropic pharmacological effects underlying their cardiovascular and renal benefits are not completely understood but include significant effects beyond blood glucose reduction. SGLT2is inhibit the reabsorption of glucose and sodium in the proximal tubule which, in addition to lowering blood glucose, activates tubuloglomerular feedback, leading to reduced glomerular hydrostatic pressure and the mitigation of glomerular filtration rate loss. SGLT2is have diuretic and natriuretic effects, leading to decreased blood pressure, preload, and left ventricular (LV) filling pressure, and improvements in other surrogates of afterload. In HF, SGLT2is mitigate the risks of hyperkalemia and ventricular arrhythmia and improve LV dysfunction. SGLT2is also reduce sympathetic tone and uric acid levels, increase hemoglobin levels, and are postulated to have anti-inflammatory properties. This narrative review discusses the multifactorial and interrelated pharmacological mechanisms underlying the cardiovascular and renal benefits of SGLT2is.

Oral empagliflozin-loaded tri-layer core-sheath fibers fabricated using tri-axial electrospinning: Enhanced in vitro and in vivo antidiabetic performance

Empagliflozin (EM) was successfully loaded in polycaprolactone/poly (L-lactic acid)/polymethyl methacrylate (PCL/PLA/PMMA) fibers. In the rat β-cell line (BRIN-BD11), the insulin expression ratio of pancreatic β-cells was stimulated at high and low glucose by culturing with tri-layer EM-loaded fiber (EMF) for 48 h. The expression ratios of glucokinase and GLUT-2 proteins increased after EMF treatment. According to the in vitro drug release test, 97% of all drug contained in fibers was released in a controlled manner for 24 h. The pharmacokinetic test revealed that the bioavailability was improved ∼4.8-fold with EMF treatment compared to EM-powder and blood glucose level was effectively controlled for 24 h with EMF. Oral administration of EMF exhibited a better sustainable anti-diabetic activity even in the half-dosage than EM-powder in streptozotocin/nicotinamide-induced T2DM rats. The levels of GLP-1, PPAR-γ, and insulin were increased while the levels of SGLT-2 and TNF-α were decreased with EMF treatment. Also, EMF recovered the histopathological changes in the liver, pancreas, and kidney in T2DM rats and protected pancreatic β-cells. Consequently, EMF is suggested as an unprecedented and promotive treatment approach for T2DM with a higher bioavailability and better antidiabetic effect compared to conventional dosage forms.

SGLT2 Inhibitor—Dapagliflozin Attenuates Diabetes-Induced Renal Injury by Regulating Inflammation through a CYP4A/20-HETE Signaling Mechanism

Diabetic kidney disease (DKD) is a serious complication of diabetes, affecting millions of people worldwide. Inflammation and oxidative stress are key contributors to the development and progression of DKD, making them potential targets for therapeutic interventions. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have emerged as a promising class of drugs, with evidence demonstrating that they can improve renal outcomes in people with diabetes. However, the exact mechanism by which SGLT2i exert their renoprotective effects is not yet fully understood. This study demonstrates that dapagliflozin treatment attenuates renal injury observed in type 2 diabetic mice. This is evidenced by the reduction in renal hypertrophy and proteinuria. Furthermore, dapagliflozin decreases tubulointerstitial fibrosis and glomerulosclerosis by mitigating the generation of reactive oxygen species and inflammation, which are activated through the production of CYP4A-induced 20-HETE. Our findings provide insights onto a novel mechanistic pathway by which SGLT2i exerts their renoprotective effects. Overall, and to our knowledge, the study provides critical insights into the pathophysiology of DKD and represents an important step towards improving outcomes for people with this devastating condition.

The protective effects of SGLT-2 inhibitors, GLP-1 receptor agonists, and RAAS blockers against renal injury in patients with type 2 diabetes

Diabetic kidney disease is one of the most severe complications of type 2 diabetes mellitus. Patients with diabetic kidney disease have a worse prognosis in terms of mortality and morbidity, compared with patients who have diabetes alone. Strict control of blood pressure and blood glucose is the primary method for prevention of initial kidney damage and delaying further progression of existing damage. Other management approaches include the use of exogenous drugs that can effectively protect the kidneys from diabetes, such as sodium-glucose transporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and renin-angiotensin-aldosterone system blockers. These drugs may protect against kidney injury through various molecular mechanisms. This review focuses on renal impairment in patients with type 2 diabetes; it discusses the direct and indirect effects of sodium-glucose transporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and renin-angiotensin-aldosterone system blockers on diabetic kidney disease. Finally, it discusses the effects of combination treatment with two or three types of drugs in patients with chronic kidney disease.

The Qi-Bang-Yi-Shen formula ameliorates renal dysfunction and fibrosis in rats with diabetic kidney disease <em>via</em> regulating PI3K/AKT, ERK and PPARγ signaling pathways

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease (CKD) and a growing public health problem worldwide. Losartan potassium (Los), an angiotensin II receptor blocker, has been used to treat DKD clinically. Recently, multi-herbal formula has been shown to exhibit therapeutic activities in DKD in China. Thus, we aimed to explore the protective effects of combination of Los and Qi-Bang-Yi-Shen formula (QBF) on DKD rats. Streptozotocin (STZ) injection was used to establish a rat model of DKD. Next, the bloodurea nitrogen (BUN), creatinine (CRE) and uric acid (UA) levels were detected in serum samples from DKD rats. Hematoxylin and eosin (H&E), periodic Acid Schiff (PAS) and Masson staining were performed to observe glomerular injury and glomerular fibrosis in DKD rats. In this study, we found that QBF or Los treatment could decrease serum BUN, CRE, UA levels and reduce urine albumin-to-creatinine ratio (ACR) in DKD rats. Additionally, QBF or Los treatment obviously inhibited glomerular mesangial expansion and glomerular fibrosis, attenuated glomerular injury in kidney tissues of DKD rats. Moreover, QBF or Los treatment significantly reduced PI3K, AKT and ERK1/2 protein expressions, but increased PPARγ level in kidney tissues of DKD rats. As expected, combined treatment of QBF and Los could exert enhanced reno-protective effects compared with the single treatment. Collectively, combination of QBF and Los could ameliorate renal injury and fibrosis in DKD rats via regulating PI3K/AKT, ERK and PPARγ signaling pathways. These findings highlight the therapeutic potential of QBF to prevent DKD progression.

Emerging Role of Sodium-Glucose Co-Transporter 2 Inhibitors for the Treatment of Chronic Kidney Disease

Chronic kidney disease is one of the leading causes of morbidity and mortality in the Philippines. It is associated with a growing health burden as many patients progress to end-stage renal disease. Until recently, therapeutic options for the management of chronic kidney disease were limited. Sodium-glucose co-transporter 2 inhibitors offer an alternative therapeutic approach for patients with chronic kidney disease. Several trials have shown renal benefits with sodium-glucose co-transporter 2 inhibitors in patients with cardiovascular disease with and without type 2 diabetes and across a range of estimated glomerular filtration rate levels. In the Philippines, the sodium-glucose co-transporter 2 inhibitors dapagliflozin and canagliflozin are approved for the prevention of new and worsening nephropathy in type 2 diabetes. With emerging treatment options, an urgent need exists for guidance on the management of chronic kidney disease within the Philippines. In this review, we focus on the putative renal-protective mechanisms of sodium-glucose co-transporter 2 inhibitors, including effects on tubuloglomerular feedback, albuminuria, endothelial function, erythropoiesis, uric acid levels, renal oxygen demand, and hypoxia. Furthermore, we discuss the findings of recent large clinical trials using sodium-glucose co-transporter 2 inhibitors in patients with chronic kidney disease and diabetic kidney disease, summarize safety aspects, and outline the practical management of patients with chronic kidney disease in the Philippines.

Narrative Review of glycaemic management in people with diabetes on peritoneal dialysis

There is an increasing number of people with diabetes on peritoneal dialysis (PD) worldwide. However, there is a lack of guidelines and clinical recommendations for managing glucose control in people with diabetes on PD. The aim of this review is to provide a summary of the relevant literature and highlight key clinical considerations with practical aspects in the management of diabetes in people undergoing PD. A formal systematic review was not conducted because of the lack of sufficient and suitable clinical studies. A literature search was performed using PubMed, MEDLINE, Central, Google Scholar and ClinicalTrials.gov., from 1980 through February 2022. The search was limited to publications in English. This narrative review and related guidance have been developed jointly by diabetologists and nephrologists, who reviewed all available current global evidence regarding the management of diabetes in people on PD.We focus on the importance of individualized care for people with diabetes on PD, the burden of hypoglycemia, glycemic variability in the context of PD and treatment choices for optimizing glucose control. In this review, we have summarized the clinical considerations to guide and inform clinicians providing care for people with diabetes on PD.

Empagliflozin attenuates the renal tubular ferroptosis in diabetic kidney disease through AMPK/NRF2 pathway

Renal tubular damage plays a key role in the pathogenesis of diabetic kidney disease (DKD), and one of the main pathological process associated with DKD in diabetic mice is the ferroptosis, a novel form of cell death caused by iron-dependent lipid peroxidation. Several researches suggested that empagliflozin may treat renal injury, but its effects on diabetic-related ferroptosis and underlying mechanisms were not fully elucidated. In this study, the influence of empagliflozin on renal injury was evaluated in vivo and in vitro in a mouse model and in high-glucose (HG) or Erastin-stimulated renal HK-2 cell line, respectively. Ferroptosis-related markers were assessed, including GSH, labile iron levels, and ferroptosis regulators by Western blot, qRT-PCR, immunohistochemistry, and immunofluorescence. The level of malondialdehyde (MDA) and the fluorescence intensity of BODIPY probe indicated the level of lipid peroxidation. It was demonstrated that solute carrier family 7, member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) were less expressed in renal biopsy samples from patients affected by DKD than in those from non-diabetic renal disease patients (NDRD), proving the ferroptosis of tubular epithelial cells in case of DKD. Furthermore, empagliflozin markedly decreased the ferroptosis impairment in DKD mice, as well as in HG model of HK-2 cells. Our investigations showed the ability of empagliflozin to suppress ferroptosis was partially countered by AMP-activated protein kinase (AMPK) inhibitor, which led to a reduction of the nuclear translocation of the antioxidant transcription factor NFE2-related factor 2 (NRF2) and downregulation of target genes such as GPX4, ferritin heavy chain 1 (FTH1), and SLC7A11, while AMPK agonists were responsible for the enhancement of the protective effects of empagliflozin. Taken together, our findings showed that empagliflozin may prevent the development of ferroptosis by promoting the AMPK-mediated NRF2 activation pathway, providing important insights for possible novel treatment approaches for DKD.

Canagliflozin reduces proteinuria by targeting hyperinsulinaemia in diabetes patients with heart failure: A post hoc analysis of the CANDLE trial

AIM

To investigate factors associated with proteinuria regression in patients with type 2 diabetes mellitus (T2DM) treated with canagliflozin.

MATERIALS AND METHODS

This study was a post hoc analysis of the CANDLE trial (UMIN000017669), which compared the effect of 24 weeks of treatment with canagliflozin or glimepiride for changes in N-terminal pro-brain natriuretic peptide in patients with T2DM and chronic heart failure (CHF). Factors associated with regression of proteinuria at 24 weeks were evaluated with multivariate logistic models.

RESULTS

The rate of regression of proteinuria was higher (28/102, 27.5% vs. 12/112, 10.7%), and that of progression was lower (9/102, 8.8% vs. 26/112, 23.2%), in the canagliflozin versus the glimepiride group (P = .0001). There were no differences in the change in the estimated glomerular filtration rate category between groups. Insulin level, homeostatic model assessment of β-cell function, homeostatic model assessment for insulin resistance and estimated plasma volume were decreased at 24 weeks in the regression subclass but not in the progression subclass, suggesting that regression of proteinuria is associated with the declines in these values in the canagliflozin group. Higher insulin level at baseline was solely associated with proteinuria regression in the multivariate logistic regression model (baseline insulin, as per a 1-mlU/L increase, odds ratio 1.24 [1.05-1.47], P = .011).

CONCLUSIONS

In patients with T2DM and CHF, regression of proteinuria with canagliflozin treatment was associated with the pretreatment insulin level. These results may provide clinicians with novel mechanistic insights into the beneficial effects of canagliflozin on renal outcomes and may warrant discussion for selecting preferred patient profiles, including pretreatment insulin levels.

Simultaneous SGLT2 inhibition and caloric restriction improves insulin resistance and kidney function in OLETF rats

SGLT2 inhibitors (SGLT2i) are emerging as a novel therapy for type 2 diabetes due to their effective hypoglycemic and potential cardio- and nephroprotective effects, while caloric restriction (CR) is a common behavioral modification to improve adiposity and insulin resistance. Therefore, both interventions simultaneously may potentially further improve metabolic syndrome by enhancing carbohydrate metabolism. To test this hypothesis, cohorts of 10-week old, male Long Evans Tokushima Otsuka (LETO) and Otsuka Long Evans Tokushima Fatty (OLETF) rats were treated with SGLT2i (10 mg luseoglifozin/kg/day x 4 wks) (OLETF only) and/or 30% CR (2 wks at 12 weeks of age). CR maintained body mass in both strains while SGLT2i alone did not have any effect on body mass. Simultaneous treatments decreased SBP in OLETF vs SGLT2i alone, decreased insulin resistance index (IRI), and increased creatinine clearance vs OLETF ad lib. Conversely, CR decreased albuminuria independent of SGLT2i. In conclusion, SGLT2i treatment by itself did not elicit significant improvements in insulin resistance, kidney function or blood pressure. However, when combined with CR, these changes where more profound than with CR alone without inducing chronic hypoglycemia.

Dapagliflozin Treatment Augments Bioactive Phosphatidylethanolamine Concentrations in Kidney Cortex Membrane Fractions of Hypertensive Diabetic db/db Mice and Alters the Density of Lipid Rafts in Mouse Proximal Tubule Cells

In addition to inhibiting renal glucose reabsorption and allowing for glucose excretion, the sodium/glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin may be efficacious in treating various comorbidities associated with type 2 diabetes mellitus (T2DM). The molecular mechanisms by which dapagliflozin exerts its beneficial effects are largely unknown. We hypothesized dapagliflozin treatment in the diabetic kidney alters plasma membrane lipid composition, suppresses extracellular vesicle (EV) release from kidney cells, and disrupts lipid rafts in proximal tubule cells. In order to test this hypothesis, we treated diabetic db/db mice with dapagliflozin (N = 8) or vehicle (N = 8) and performed mass spectrometry-based lipidomics to investigate changes in the concentrations of membrane lipids in the kidney cortex. In addition, we isolated urinary EVs (uEVs) from urine samples collected during the active phase and the inactive phase of the mice and then probed for changes in membrane proteins enriched in the EVs. Multiple triacylglycerols (TAGs) were enriched in the kidney cortex membrane fractions of vehicle-treated diabetic db/db mice, while the levels of multiple phosphatidylethanolamines were significantly higher in similar mice treated with dapagliflozin. EV concentration and size were lesser in the urine samples collected during the inactive phase of dapagliflozin-treated diabetic mice. In cultured mouse proximal tubule cells treated with dapagliflozin, the lipid raft protein caveolin-1 shifted from less dense fractions to more dense sucrose density gradient fractions. Taken together, these results suggest dapagliflozin may regulate lipid-mediated signal transduction in the diabetic kidney.

Cardiovascular and renal outcomes among patients with type 2 diabetes using SGLT2 inhibitors added to metformin: a population-based cohort study from the UK

INTRODUCTION

Large numbers of patients with type 2 diabetes receive treatment with a sodium-glucose co-transporter-2 inhibitor (SGLT2i). We investigated whether the cardiorenal preventative effects found in clinical trials are also seen in clinical practice where patient characteristics and adherence to treatment differ.

RESEARCH DESIGN AND METHODS

Using UK primary care electronic health records, we followed two cohorts of patients with type 2 diabetes prescribed metformin: SGLT2is (N=12 978) and a matched comparator of patients not using an SGLT2i at the start of follow-up (N=44 286). Independent follow-ups were performed to identify the study outcomes: cardiovascular (CV) composite (comprising non-fatal myocardial infarction (MI)/ischemic stroke (IS) requiring hospitalization and CV death), severe renal disease, and all-cause mortality. Cox regression was used to estimate adjusted HRs.

RESULTS

Mean follow-up was 2.3 years (SGLT2i cohort) and 2.1 years (comparison cohort). Mean age was 59.6 years (SD ±10.2, SGLT2i cohort) and 60.4 years (SD ±10.0, comparison cohort). SGLT2i new users were associated with a reduced risk of the CV composite (HR 0.75, 95% CI: 0.61 to 0.93), severe renal disease (HR 0.55, 95% CI: 0.46 to 0.67), and all-cause mortality (HR 0.56, 95% CI: 0.49 to 0.63), with risk reductions similar irrespective of baseline chronic kidney disease. Reduced risks were seen for IS (HR 0.51, 95% CI: 0.36 to 0.74) but not MI (HR 0.98, 95% CI: 0.74 to 1.28). Results were consistent in sensitivity analyses.

CONCLUSIONS

In this population-based study, SGLT2is were associated with significant CV, renal and survival benefits among individuals with type 2 diabetes on metformin; the CV benefit was driven by a reduced risk of ischemic stroke.

Effect of sodium-glucose cotransporter 2 inhibitors on the rate of decline in kidney function: A systematic review and meta-analysis

AIM

To investigate the influence of sodium/glucose cotransporter-2 inhibitors (SGLT-2i) on renal function during the course of its administration, particularly in the initial weeks.

MATERIALS AND METHODS

Randomized controlled trials (RCTs) related to SGLT-2i were searched in databases (MEDLINE, EMBASE, and Cochrane Central Register) from the database's inception to August 31, 2021. All RCTs reported the kidney outcomes of SGLT2i versus active or placebo control were included, regardless of the presence of diabetes in the patients and the baseline estimated glomerular filtration rate (eGFR). The Cochrane Collaboration risk of bias tool was used to assess the quality of the included studies. All outcome comparisons were performed using the RevMan 5.4 software.

RESULTS

Eleven RCTs with 58 534 participants reporting prespecified renal outcomes were identified. There was no heterogeneity in the baseline eGFR and urine albumin-to-creatinine ratio in the included studies. In the initial 2-4 weeks, there was an acute decline of eGFR in the SGLT-2i group compared with placebo group (weighted mean difference [WMD] -3.35 ml/min/1.73 m² ; 95% CI, -3.81 to -2.90; I²  = 35%, p = .15); When compared to baseline eGFR in the SGLT-2i group, the WMD was -4.02 ml/min/1.73 m² (95% confidence interval [CI], -3.61 to -4.44; I²  = 0%, p = .45). The renoprotective effect gradually appeared, and the decline rate of eGFR in the SGLT-2i group was sustained slower than placebo. However, the statistically significant benefit of SGLT-2i did not appear until the 104th week (the second year) (WMD 0.35 ml/min/1.73 m² , 95% CI, 0.04 to 0.66; I²  = 45%, p = .08). Subgroup analysis showed SGLT-2i had a similar benefit on renal function regardless of baseline eGFR values.

CONCLUSION

SGLT-2i consistently slowed the deterioration of eGFR since the early stage of administration, even in patients with chronic kidney disease. However, there was an acute decline in eGFR in the initial 2-4 weeks; afterwards the renoprotective effect of SGLT-2i gradually appeared and remained stable in the next few years.

Molecular programs associated with glomerular hyperfiltration in early diabetic kidney disease

Hyperfiltration is a state of high glomerular filtration rate (GFR) observed in early diabetes that damages glomeruli, resulting in an iterative process of increasing filtration load on fewer and fewer remaining functional glomeruli. To delineate underlying cellular mechanisms of damage associated with hyperfiltration, transcriptional profiles of kidney biopsies from Pima Indians with type 2 diabetes with or without early-stage diabetic kidney disease were grouped into two hyperfiltration categories based on annual iothalamate GFR measurements. Twenty-six participants with a peak GFR measurement within two years of biopsy were categorized as the hyperfiltration group, and 26 in whom biopsy preceded peak GFR by over two years were considered pre-hyperfiltration. The hyperfiltration group had higher hemoglobin A1c, higher urine albumin-to-creatinine ratio, increased glomerular basement membrane width and lower podocyte density compared to the pre-hyperfiltration group. A glomerular 1240-gene transcriptional signature identified in the hyperfiltration group was enriched for endothelial stress response signaling genes, including endothelin-1, tec-kinase and transforming growth factor-β1 pathways, with the majority of the transcripts mapped to endothelial and inflammatory cell clusters in kidney single cell transcriptional data. Thus, our analysis reveals molecular pathomechanisms associated with hyperfiltration in early diabetic kidney disease involving putative ligand-receptor pairs with downstream intracellular targets linked to cellular crosstalk between endothelial and mesangial cells.

A modular and reusable model of epithelial transport in the proximal convoluted tubule

We review a collection of published renal epithelial transport models, from which we build a consistent and reusable mathematical model able to reproduce many observations and predictions from the literature. The flexible modular model we present here can be adapted to specific configurations of epithelial transport, and in this work we focus on transport in the proximal convoluted tubule of the renal nephron. Our mathematical model of the epithelial proximal convoluted tubule describes the cellular and subcellular mechanisms of the transporters, intracellular buffering, solute fluxes, and other processes. We provide free and open access to the Python implementation to ensure our multiscale proximal tubule model is accessible; enabling the reader to explore the model through setting their own simulations, reproducibility tests, and sensitivity analyses.

Knowledge domain and emerging trends in empagliflozin for heart failure: A bibliometric and visualized analysis

Objective

Empagliflozin (EMPA), a sodium-glucose cotransporter 2 inhibitor (SGLT2i), is recommended for all patients with Heart failure (HF) to reduce the risk of Cardiovascular death, hospitalization, and HF exacerbation. Qualitative and quantitative evaluation was conducted by searching relevant literatures of EMPA for Heart Failure from 2013 to 2022, and visual analysis in this field was conducted.

Methods

The data were from the Web of Science Core Collection database (WOSCC). The bibliometric tools, CiteSpace and VOSviewer, were used for econometric analysis to probe the evolvement of disciplines and research hotspots in the field of EMPA for Heart Failure.

Results

A total of 1461 literatures with 43861 references about EMPA for Heart Failure in the decade were extracted from WOSCC, and the number of manuscripts were on a rise. In the terms of co-authorship, USA leads the field in research maturity and exerts a crucial role in the field of EMPA for Heart Failure. Multidisciplinary research is conducive to future development. With regards to literatures, we obtained 9 hot paper, 93 highly cited literatures, and 10 co-cited references. The current research focuses on the following three aspects: EMPA improves left ventricular remodeling, exert renal protection, and increases heart rate variability.

Conclusion

Based on methods such as bibliometrics, citation analysis and knowledge graph, this study analyzed the current situation and trend of EMPA for Heart Failure, sorted out the knowledge context in this field, and provided reference for current and future prevention and scientific research.

Diabetic Nephropathy: Pathogenesis to Cure

Diabetic nephropathy (DN) is a leading cause of end-stage renal disorder (ESRD). It is defined as the increase in urinary albumin excretion (UAE) when no other renal disease is present. DN is categorized into microalbuminuria and macroalbuminuria. Factors like high blood pressure, high blood sugar levels, genetics, oxidative stress, hemodynamic and metabolic changes affect DN. Hyperglycemia causes renal damage through activating protein kinase C (PKC), producing advanced end glycation products (AGEs) and reactive oxygen species (ROS). Growth factors, chemokines, cell adhesion molecules, inflammatory cytokines are found to be elevated in the renal tissues of the diabetic patient. Many different and new diagnostic methods and treatment options are available due to the increase in research efforts and progression in medical science. However, until now, no permanent cure is available. This article aims to explore the mechanism, diagnosis, and therapeutic strategies in current use for increasing the understanding of DN.

Safety of sodium-glucose cotransporter 2 inhibitors in Asian type 2 diabetes populations

The prevalence of type 2 diabetes mellitus continues to increase in many Asian countries, with possible contributing factors, such as younger-onset disease, diabetes development at lower body mass index, higher visceral fat accumulation and poorer β-cell function, among Asian populations. Sodium-glucose cotransporter 2 inhibitors have been shown to confer favorable effects in type 2 diabetes mellitus patients, such as improved glycemic control, weight and blood pressure reduction, and importantly, cardiorenal benefits. Sodium-glucose cotransporter 2 inhibitors are generally well-tolerated, and have a well-defined safety profile based on evidence from numerous clinical trials and post-marketing pharmacovigilance reporting. To our knowledge, this review is the first to provide a comprehensive coverage of the adverse events of sodium-glucose cotransporter 2 inhibitors, as well as their management and counseling aspects for Asian type 2 diabetes mellitus populations.

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.