The kidney and type 2 diabetes mellitus: therapeutic implications of SGLT2 inhibitors

Antibacterial, antidiabetic and antioxidant bioevaluation of Calamus leptospadix Griff. and isolation of a flavan type compound

The plant based natural products have always been a rich source of bioactive molecules for drug discovery. The tender shoots of Calamus leptospadix Griff., an edible medicinal plant was extracted using methanol, water and ethanol as three different solvents to study the effect of the extracting solvents and temperature on their antioxidant, antidiabetic and antibacterial properties and total phenolic and flavonoid contents. The antioxidant properties were determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assay. The α-glucosidase inhibitory assay was carried out to determine the antidiabetic potential. The antibacterial properties of the extracts were determined against four strains of bacterial species viz. Bacillus subtilis, Streptococcus pneumoniae, Escherichia coli and Citrobacter freundii using Broth macro dilution method. The methanolic extracts of the plant were found to possess the highest total phenolic and total flavonoid contents. In the antioxidant assays, the cold methanolic extract was found to exhibit the highest DDPH radical scavenging activity and ferric-reducing antioxidant power. In the antidiabetic assay, the extract exhibited better α-glucosidase inhibitory potential than that of the positive control acarbose. It was also found to be effective against both gram-positive and gram-negative strains in the antibacterial assay. A flavan-type compound 4-(5,7-dimethoxychroman-2-yl)phenol was isolated from the most bioactive cold methanolic extract of the plant and characterised from its XRD, 1H and 13C NMR, HRMS and IR data.

Efficacy and safety of sodium-glucose cotransporter-2 inhibitors in patients with chronic kidney disease: a systematic review and meta-analysis

PURPOSE

Owing to the pharmacological mechanism, sodium-glucose cotransporter 2 inhibitors (SGLT2is) may be less effective in patients with reduced renal functions, but no systematic review or meta-analysis addressed chronic kidney disease (CKD) patients specifically. We aimed to assess the efficacy and safety of SGLT2is in CKD patients.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials. Mean difference (MD) were pooled for the decline of glomerular filtration rate (eGFR) and change in urine albumin-to-creatinine ratio (uACR). Hazard ratio (HR) and rate ratio (RR) were pooled for composite of renal outcomes and adverse effects.

RESULTS

Thirty articles were identified. Overall MD in rate of eGFR decline was 0.02 (P = 0.05), with a borderline significant difference favoring SGLT2is, while the change in uACR from baseline was - 141.34 mg/g and hazard ratio of composite renal outcomes was 0.64 significantly favoring SGLT2is. Subgroup analyses showed that the long-term renal function, participants with baseline macroalbuminuria, and stage 4 CKD patients had significantly slower eGFR decline rate in SGLT2is compared to the placebo group. Risks of genital mycotic infection and ketoacidosis were significantly higher among the SGLT2is group than placebo.

CONCLUSION

For CKD patients, no matter diabetic or non-diabetic, our study showed potential renoprotective effects favoring SGLT2is in overall and long-term phase, and in patients with macroalbuminuria or stage 4 CKD. However, only slight increased risk of adverse effects among the SGLT2is group is observed. Therefore, we concluded that in CKD patients, prescribing SGLT2is was safe and had renal benefits.

An Update on the Molecular and Cellular Basis of Pharmacotherapy in Type 2 Diabetes Mellitus

Diabetes mellitus (DM) is a chronic illness with an increasing global prevalence. More than 537 million cases of diabetes were reported worldwide in 2021, and the number is steadily increasing. The worldwide number of people suffering from DM is projected to reach 783 million in 2045. In 2021 alone, more than USD 966 billion was spent on the management of DM. Reduced physical activity due to urbanization is believed to be the major cause of the increase in the incidence of the disease, as it is associated with higher rates of obesity. Diabetes poses a risk for chronic complications such as nephropathy, angiopathy, neuropathy and retinopathy. Hence, the successful management of blood glucose is the cornerstone of DM therapy. The effective management of the hyperglycemia associated with type 2 diabetes includes physical exercise, diet and therapeutic interventions (insulin, biguanides, second generation sulfonylureas, glucagon-like peptide 1 agonists, dipeptidyl-peptidase 4 inhibitors, thiazolidinediones, amylin mimetics, meglitinides, α-glucosidase inhibitors, sodium-glucose cotransporter-2 inhibitors and bile acid sequestrants). The optimal and timely treatment of DM improves the quality of life and reduces the severe burden of the disease for patients. Genetic testing, examining the roles of different genes involved in the pathogenesis of DM, may also help to achieve optimal DM management in the future by reducing the incidence of DM and by enhancing the use of individualized treatment regimens.

Renoprotective Effect of Thai Patients with Type 2 Diabetes Mellitus Treated with SGLT-2 Inhibitors versus DPP-4 Inhibitors: A Real-World Observational Study

Background

Recently, there is a lack of studies comparing the renoprotective effects of sodium-glucose cotransporter-2 (SGLT-2) inhibitors and dipeptidyl peptidase-4 (DPP-4) inhibitors. This study therefore aimed to investigate the renoprotective effects of SGLT-2 inhibitors and DPP-4 inhibitors on Thai patients with type 2 diabetes mellitus.

Methods

Patient medication records of all patients who used those two antidiabetic classes at Fort Wachirawut Hospital were reviewed. Renal function tests, blood glucose levels, and other baseline characteristics were collected. Continuous variables were compared within the group using the Wilcoxon signed-rank test and between groups using the Mann-Whitney U test.

Results

There were 388 and 691 patients with SGLT-2 inhibitors and DPP-4 inhibitors, respectively. The mean estimated glomerular filtration rate (eGFR) of the SGLT-2 inhibitor group was significantly lower from baseline at 18 months of treatment, as well as the DPP-4 inhibitor group. However, the trend of eGFR reduction in patients with baseline eGFR <60 mL/min/1.73 m² was smaller than those with baseline eGFR ≥60 mL/min/1.73 m². In addition, the fasting blood sugar and haemoglobin A1c levels significantly decreased from baseline in both the groups.

Conclusions

Both SGLT-2 inhibitors and DPP-4 inhibitors showed the same trends of eGFR reductions from baseline in Thai patients with type 2 diabetes mellitus. However, SGLT-2 inhibitors should be considered in patients with impaired renal function rather than in all T2DM patients.

Associations of waist-to-height ratio with the incidence of type 2 diabetes and mediation analysis: Two independent cohort studies

AIM

To assess the relationship between waist-to-height ratio (WHtR) and the incidence of type 2 diabetes (T2D)/impaired fasting glucose (IFG) and to explore to what extent these associations are mediated by blood pressure, lipids and other indicators related to liver and kidney metabolism.

MATERIALS AND METHODS

This study was based on a functional community cohort included 6109 participants which were divided into two sub-cohorts. One sub-cohort included participants with normal fasting glucose (n = 5563), another included IFG individuals at baseline (n = 546). Cox regression models were used to evaluate the relationships of WHtR with T2D/IFG. Four-year time-dependent receiver operating characteristic (ROC) curve and area under curve (AUC) were calculated to estimate the discriminatory power of WhtR and other anthropometric indices on T2D. Mediation analysis was performed to estimate which risk factors mediate the association between WHtR and T2D.

RESULTS

Significant positive associations were found between WHtR and the incidence of T2D/IFG in both sub-cohort. WhtR was a useful predictor of T2D (P < 0.05). Mediation analysis showed that HOMA-IR (0.45 %), SBP (5.10 %), triglycerides (11.02 %), creatinine (9.36 %) and combined kidney indicators (17.48 %) partly mediated the effect of WHtR on T2D in men. For women, this association was partly mediated by SBP (13.86 %), HDL (24.54 %), ALT (6.29 %), UA (22.58 %) and combined kidney indicators (39.51 %).

CONCLUSIONS

WHtR was an independent risk factor for the development of T2D and IFG. This association was partly mediated by HOMA-IR, SBP, lipids and other liver and kidney metabolism indicators.

In Vitro and In Vivo Antidiabetic Potential of Monoterpenoids: An Update

Diabetes mellitus (DM) is a chronic metabolic condition characterized by persistent hyperglycemia due to insufficient insulin levels or insulin resistance. Despite the availability of several oral and injectable hypoglycemic agents, their use is associated with a wide range of side effects. Monoterpenes are compounds extracted from different plants including herbs, vegetables, and fruits and they contribute to their aroma and flavor. Based on their chemical structure, monoterpenes are classified into acyclic, monocyclic, and bicyclic monoterpenes. They have been found to exhibit numerous biological and medicinal effects such as antipruritic, antioxidant, anti-inflammatory, and analgesic activities. Therefore, monoterpenes emerged as promising molecules that can be used therapeutically to treat a vast range of diseases. Additionally, monoterpenes were found to modulate enzymes and proteins that contribute to insulin resistance and other pathological events caused by DM. In this review, we highlight the different mechanisms by which monoterpenes can be used in the pharmacological intervention of DM via the alteration of certain enzymes, proteins, and pathways involved in the pathophysiology of DM. Based on the fact that monoterpenes have multiple mechanisms of action on different targets in in vitro and in vivo studies, they can be considered as lead compounds for developing effective hypoglycemic agents. Incorporating these compounds in clinical trials is needed to investigate their actions in diabetic patients in order to confirm their ability in controlling hyperglycemia.

What Makes Sodium-Glucose Co-Transporter-2 Inhibitors Stand out in Heart Failure?

PURPOSE OF REVIEW

We highlight the unique properties of the sodium-glucose cotransporter-2 (SGLT-2 inhibitors) which may lend favorably to their efficient integration in the background of other heart failure (HF) therapies. We also discuss the unique aspects of SGLT-2 inhibitor dosing, lack of titration needs, effects on kidney function and electrolytes, diuretic activity, and safety in the high-risk peri-hospitalization window.

RECENT FINDINGS

Dapagliflozin was recently approved for the treatment of heart failure with reduced ejection fraction (HFrEF), irrespective of the presence or absence of type 2 diabetes mellitus (T2DM) based on the findings of the pivotal DAPA-HF trial. All SGLT-2 inhibitors are once daily medications with minimal drug-drug interactions and do not require titration (for HF treatment) unlike other HF medications. SGLT-2 inhibitors offer modest weight loss and blood pressure reduction without major adverse effects of hyperkalemia, making it ideal for near-simultaneous initiation with other HF medications, and use in high-risk populations (including older adults). Moreover, SGLT-2 inhibitors appear to afford long-term kidney protection in diverse populations. SGLT-2 inhibitors are the latest class of therapies to demonstrate important clinical benefits among patients with HFrEF, and their pharmacological properties favor ease of use and integration in multi-drug disease-modifying regimens.

Functional loss of pancreatic islets in type 2 diabetes: How can we halt it?

The loss of beta-cell functional mass is a necessary and early condition in the development of type 2 diabetes (T2D). In T2D patients, beta-cell function is already reduced by about 50% at diagnosis and further declines thereafter. Beta-cell mass is also reduced in subjects with T2D, and islets from diabetic donors are smaller compared to non-diabetic donors. Thus, beta-cell regeneration and/or preservation of the functional islet integrity should be highly considered for T2D treatment and possibly cure. To date, the available anti-diabetes drugs have been developed as "symptomatic" medications since they act to primarily reduce elevated blood glucose levels. However, a truly efficient anti-diabetes medication, capable to prevent the onset and progression of T2D, should stop beta-cell loss and/or promote the restoration of fully functional beta-cell mass, independently of reducing hyperglycemia and ameliorating glucotoxicity on the pancreatic islets. This review provides a view of the experimental and clinical evidence on the ability of available anti-diabetes drugs to exert protective effects on beta-cells, with a specific focus on human pancreatic islets and clinical trials. Potential explanations for the lack of concordance between evidence of beta-cell protection in vitro and of persistent amelioration of beta-cell function in vivo are also discussed.

Canagliflozin for the Treatment of Diabetic Kidney Disease and Implications for Clinical Practice: A Narrative Review

Type 2 diabetes mellitus (T2DM) affects millions of people worldwide, elevating their risk of developing a range of complications, including chronic kidney disease (CKD). People with T2DM and CKD (i.e., diabetic kidney disease, DKD) have an increased risk of progressing to end-stage kidney disease (ESKD), experiencing cardiovascular complications, and premature death. Despite this, DKD is primarily addressed through management of risk factors, and there are few pharmaceutical treatments capable of reversing or delaying disease progression. Canagliflozin is a sodium glucose co-transporter 2 inhibitor that was initially developed as a blood glucose-lowering agent for people with T2DM. Evidence from clinical trials of canagliflozin in people with T2DM, as well as evidence from cardiovascular outcomes trials in people with T2DM and high cardiovascular risk, provided preliminary evidence suggesting that it may also have beneficial renal effects. The Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial was a dedicated renal outcomes trial of canagliflozin that assessed its renal effects in people with DKD. Overall, the CREDENCE trial demonstrated that canagliflozin improves renal outcomes and slows early disease progression in people with DKD. These data supported the approval of canagliflozin for the treatment DKD, the first new treatment in almost 20 years; therefore, it is important for clinicians to understand how to implement this treatment in their clinical practice.

Osmotic Nephrosis and Acute Kidney Injury Associated With SGLT2 Inhibitor Use: A Case Report

We report a case of a patient who developed dialysis-requiring acute kidney injury (AKI) after the use of canagliflozin. A 66-year-old man with type 2 diabetes who was recovering from left knee septic arthritis at a rehabilitation facility was admitted with oliguric AKI 5 days after starting treatment with canagliflozin, an inhibitor of sodium/glucose cotransporter 2 (SGLT2). The patient presented with hematuria, non-nephrotic-range proteinuria, and serum creatinine level of 6.8 (baseline, 1.1-1.3) mg/dL. There was no recent use of radiocontrast agents or exposure to other nephrotoxins. The patient subsequently required hemodialysis. Due to recent antibiotic use (ampicillin-sulbactam), acute interstitial nephritis was considered in the differential diagnosis. Kidney biopsy was performed, which showed the presence of osmotic nephropathy. The patient's kidney function returned to baseline after 2 weeks of hemodialysis. This case provides evidence of an association of osmotic nephropathy with the use of canagliflozin and discusses potential mechanisms. We recommend kidney biopsy for cases of severe AKI associated with SGLT2 inhibitors to better understand the relationship of this complication with the use of this class of medications.

Renal effects of sodium-glucose cotransporter-2 inhibitors in patients with type 2 diabetes and renal impairment

In patients with type 2 diabetes (T2D), microvascular changes in the kidney often result in diabetic kidney disease (DKD), the progression of which is associated with an increased risk of cardiovascular (CV) and all-cause mortality. Sodium-glucose cotransporter-2 inhibitors (SGLT-2is) are a newer class of oral glucose-lowering therapies that were associated with significant reductions in the risk of major adverse CV events, CV death, and hospitalization for heart failure compared with placebo in CV outcomes trials (CVOTs) of patients with T2D and established CV disease or varying levels of CV risk. In addition, SGLT-2is reduced the risks of clinically relevant renal outcomes in these large randomized studies, indicating the potential for renoprotective effects in patients with T2D and DKD. This review discussed the non-glycemic effects of SGLT-2is in patients with T2D and renal impairment, including reductions in systolic and diastolic blood pressure, decreases in albuminuria and plasma uric acid, changes in estimated glomerular filtration rate, and minimal changes in electrolytes. Potential mechanisms for the renoprotective effects of SGLT-2is observed in CVOTs were considered, including the likely incremental benefits of SGLT-2is when added to renin-aldosterone-angiotensin system inhibitors (RAASis). The possibility of extending the use of SGLT-2is to patients with non-DKD was also discussed. Although the exact mechanisms by which SGLT-2is improve renal outcomes are not fully understood, they are likely to be multifactorial and additive when these drugs are used in combination with RAASis in patients with DKD.

Efficacy and renal outcomes of SGLT2 inhibitors in patients with type 2 diabetes and chronic kidney disease

OBJECTIVE

To review glucose-lowering efficacy and changes in renal function associated with sodium-glucose co-transporter 2 (SGLT2) inhibitors among patients with chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM).

DATA SOURCES

A literature search of MEDLINE and Cochrane databases was performed from 2000 to August 2018 using search terms: SGLT2 inhibitors, sodium glucose co-transporter 2, canagliflozin, empagliflozin, dapagliflozin, ertugliflozin, and chronic kidney disease. References of identified articles were also reviewed.

STUDY SELECTION AND DATA EXTRACTION

English-language studies investigating glucose-lowering endpoints and/or changes in renal function with one of four U.S. approved SGLT2 inhibitors were included. A total of 10 studies met inclusion criteria and are included in this review.

RESULTS

In patients with T2DM and CKD, SGLT2 inhibitors are modestly effective in lowering hemoglobin A1C and fasting plasma glucose compared to placebo. Small reductions in eGFR are seen shortly after initiating therapy with SGLT2 inhibitors, but return to baseline levels after discontinuation. SGLT2 inhibitors are associated with a substantial reduction in albuminuria and reduced risk of progression to albuminuria.

CONCLUSIONS

In patients with T2DM and CKD, SGLT2 inhibitors have a decreased glucose-lowering effect compared to patients without CKD. Renal benefits among patients with CKD are similar to those without CKD and include a significant reduction in albuminuria and reduced incidence of worsening albuminuria. Given that CKD and T2DM are both associated with increased cardiovascular risk, we believe these agents should considered as preferred add-on agents in most patients with uncontrolled T2DM and eGFR >30 ml/min/1.73 m². Ongoing studies will provide additional information as to whether these agents should be added to the current standard of care for CKD patients, with and without T2DM.

Recent progress of sodium-glucose transporter 2 inhibitors as potential antidiabetic agents

SGLT2 inhibitors were promising and novel antidiabetic drugs which suppressed glucose reabsorption and increased urinary glucose exertion. This review paper are aimed to summarize the recent progress of SGLT2 inhibitors during the last 5 years. This paper first summarizes the information of SGLT2 inhibitors, including mechanism, evolution and then focuses on the recent efforts on structure-activity relationships and structural optimization of SGLT2 inhibitors. Finally, the corresponding clinical therapeutic efficacy and adverse drug reaction in patients with Type 2 diabetes are discussed in detail.

Implications of the EMPA-REG Trial for Clinical Care and Research

EMPA-REG OUTCOME was a multicenter, randomized placebo-controlled trial that examined the effect of empagliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor in addition to standard of care in patients with type 2 diabetes and established cardiovascular (CV) disease. The primary goal was to assess CV safety, as mandated by the US Food and Drug Administration since 2008 for all new glucose-lowering agents. Secondary goals were to examine the effects of empagliflozin on microvascular outcomes and, in particular, kidney disease. This landmark study had several important findings, including striking reductions in the incidence of CV death and heart failure hospitalization and in the progression of renal dysfunction. In this review, we describe the trial's main findings, discuss the possible mechanisms that could explain its results, suggest ways in which clinical care may be influenced, and propose directions for future research.

Serum uric acid and acute kidney injury: A mini review

Acute kidney injury causes great morbidity and mortality in both the community and hospital settings. Understanding the etiological factors and the pathophysiological principles resulting in acute kidney injury is essential in prompting appropriate therapies. Recently hyperuricemia has been recognized as a potentially modifiable risk factor for acute kidney injury, including that associated with cardiovascular surgery, radiocontrast administration, rhabdomyolysis, and associated with heat stress. This review discussed the evidence that repeated episodes of acute kidney injury from heat stress and dehydration may also underlie the pathogenesis of the chronic kidney disease epidemic that is occurring in Central America (Mesoamerican nephropathy). Potential mechanisms for how uric acid might contribute to acute kidney injury are also discussed, including systemic effects on renal microvasculature and hemodynamics, and local crystalline and noncrystalline effects on the renal tubules. Pilot clinical trials also show potential benefits of lowering uric acid on acute kidney injury associated with a variety of insults. In summary, there is mounting evidence that hyperuricemia may have a significant role in the development of acute kidney injury. Prospective, placebo controlled, randomized trials are needed to determine the potential benefit of uric acid lowering therapy on kidney and cardio-metabolic diseases.

Update on the treatment of type 2 diabetes mellitus

To achieve good metabolic control in diabetes and keep long term, a combination of changes in lifestyle and pharmacological treatment is necessary. Achieving near-normal glycated hemoglobin significantly, decreases risk of macrovascular and microvascular complications. At present there are different treatments, both oral and injectable, available for the treatment of type 2 diabetes mellitus (T2DM). Treatment algorithms designed to reduce the development or progression of the complications of diabetes emphasizes the need for good glycaemic control. The aim of this review is to perform an update on the benefits and limitations of different drugs, both current and future, for the treatment of T2DM. Initial intervention should focus on lifestyle changes. Moreover, changes in lifestyle have proven to be beneficial, but for many patients is a complication keep long term. Physicians should be familiar with the different types of existing drugs for the treatment of diabetes and select the most effective, safe and better tolerated by patients. Metformin remains the first choice of treatment for most patients. Other alternative or second-line treatment options should be individualized depending on the characteristics of each patient. This article reviews the treatments available for patients with T2DM, with an emphasis on agents introduced within the last decade.