Effect of sodium-glucose cotransporter-2 inhibitors on aldosterone-to-renin ratio in diabetic patients with hypertension: a retrospective observational study

Emerging Perspectives on the Impact of Diabetes Mellitus and Anti-Diabetic Drugs on Premenstrual Syndrome. A Narrative Review

Diabetes mellitus (DM) and premenstrual syndrome (PMS) are global health challenges. Both disorders are often linked to a range of physical and psychological symptoms that significantly impact the quality of life of many women. Yet, the exact relation between DM and PMS is not clear, and the management of both conditions poses a considerable challenge. In this review, we aimed to investigate the interplay between DM, anti-diabetic drugs, and the different theories and symptoms of PMS. Female sex hormones are implicated in the pathophysiology of PMS and can also impair blood glucose control. In addition, patients with diabetes face a higher susceptibility to anxiety and depression disorders, with a significant number of patients experiencing symptoms such as fatigue and difficulty concentrating, which are reported in patients with PMS as well. Complications related to diabetic medications, such as hypoglycemia (with sulfonylurea) and fluid retention (with thiazolidinediones) may also mediate PMS-like symptoms. DM can, in addition, disturb the normal gut microbiota (GM), with a consequent loss of beneficial GM metabolites that guard against PMS, particularly the short-chain fatty acids and serotonin. Among the several available anti-diabetic drugs, those (1) with an anti-inflammatory potential, (2) that can preserve the beneficial GM, and (3) possessing a lower risk for hypoglycemia, might have a favorable outcome in PMS women. Yet, well-designed clinical trials are needed to investigate the anti-diabetic drug(s) of choice for patients with diabetes and PMS.

Association of anti-Ro52 autoantibody with interstitial lung disease in autoimmune diseases: a systematic review and meta-analysis

OBJECTIVES

Interstitial lung disease (ILD) is an important manifestation of autoimmune diseases that can lead to morbidity and mortality. Although several autoantibodies have been linked with ILD presentation and adverse outcomes, the association of anti-Ro52 antibody with ILD is less studied. Hence, we investigated this association in various autoimmune diseases in the current study.

DESIGN

We designed a systematic review and meta-analysis and did a comprehensive search from inception until 2 January 2023.

DATA SOURCES

A systematic search was conducted in four electronic databases: PubMed, Web of Science, Scopus and Embase.

ELIGIBILITY CRITERIA

Observational studies that reported ILD diagnosis (outcome) and anti-Ro antibody (exposure) status in any autoimmune conditions (population) were included. The association between rapidly progressive ILD (RP-ILD) and anti-Ro52 was studied in idiopathic inflammatory myopathies (IIM).

DATA EXTRACTION AND SYNTHESIS

Collected data included study characteristics and ORs with 95% CIs. Quality assessment was performed using a modified version of the Newcastle-Ottawa Scale for cross-sectional studies. Random effects meta-analysis was used to pool the effect estimates.

RESULTS

A total of 2353 studies were identified, from which 59 articles met the eligibility criteria. Anti-Ro52/SSA positivity was associated with ILD in all autoimmune disease subgroups: IIM (OR=3.08; 95% CI: 2.18 to 4.35; p value<0.001; I2=49%), systemic lupus (OR=2.43; 95% CI: 1.02 to 5.79; p=0.046; I2=71%), Sjogren (OR=1.77; 95% CI: 1.09 to 2.87; p=0.021; I2=73%), systemic sclerosis (OR=1.71; 95% CI: 1.04 to 2.83; p=0.036; I2=43%), mixed connective tissue disease (OR=3.34; 95% CI: 1.82 to 6.13; p<0.001; I2=0%). Additionally, anti-Ro52-positive myopathy patients were more likely to have simultaneous RP-ILD (OR=2.69; 95% CI:1.50 to 4.83; p<0.001; I2=71%).

CONCLUSION

Anti-Ro52/SSA positivity is associated with a higher frequency of ILD diagnosis in various autoimmune diseases. Anti-Ro52/SSA is also linked with a more severe lung involvement (RP-ILD). Future studies can investigate the benefits of screening for anti-Ro52 and its association with ILD development.

PROSPERO REGISTRATION NUMBER

CRD42022381447.

Renal Oxygen Demand and Nephron Function: Is Glucose a Friend or Foe?

The kidneys and heart work together to balance the body's circulation, and although their physiology is based on strict inter dependence, their performance fulfills different aims. While the heart can rapidly increase its own oxygen consumption to comply with the wide changes in metabolic demand linked to body function, the kidneys physiology are primarily designed to maintain a stable metabolic rate and have a limited capacity to cope with any steep increase in renal metabolism. In the kidneys, glomerular population filters a large amount of blood and the tubular system has been programmed to reabsorb 99% of filtrate by reabsorbing sodium together with other filtered substances, including all glucose molecules. Glucose reabsorption involves the sodium-glucose cotransporters SGLT2 and SGLT1 on the apical membrane in the proximal tubular section; it also enhances bicarbonate formation so as to preserve the acid-base balance. The complex work of reabsorption in the kidney is the main factor in renal oxygen consumption; analysis of the renal glucose transport in disease states provides a better understanding of the renal physiology changes that occur when clinical conditions alter the neurohormonal response leading to an increase in glomerular filtration pressure. In this circumstance, glomerular hyperfiltration occurs, imposing a higher metabolic demand on kidney physiology and causing progressive renal impairment. Albumin urination is the warning signal of renal engagement over exertion and most frequently heralds heart failure development, regardless of disease etiology. The review analyzes the mechanisms linked to renal oxygen consumption, focusing on sodium-glucose management.

Sodium-glucose cotransporter inhibitors and kidney fibrosis: review of the current evidence and related mechanisms

Sodium-glucose cotransporter inhibitors (SGLT2i) are a new class of anti-diabetic drugs that have beneficial cardiovascular and renal effects. These drugs decrease proximal tubular glucose reabsorption and decrease blood glucose levels as a main anti-diabetic action. Furthermore, SGLT2i decreases glomerular hyperfiltration by a tubuloglomerular feedback mechanism. However, the renal benefits of these agents are independent of glucose-lowering and hemodynamic factors, and SGLT2i also impacts the kidney structure including kidney fibrosis. Renal fibrosis is a common pathway and pathological marker of virtually every type of chronic kidney disease (CKD), and amelioration of renal fibrosis is of utmost importance to reduce the progression of CKD. Recent studies have shown that SGLT2i impact many cellular processes including inflammation, hypoxia, oxidative stress, metabolic functions, and renin-angiotensin system (RAS) which all are related with kidney fibrosis. Indeed, most but not all studies showed that renal fibrosis was ameliorated by SGLT2i through the reduction of inflammation, hypoxia, oxidative stress, and RAS activation. In addition, less known effects on SGLT2i on klotho expression, capillary rarefaction, signal transducer and activator of transcription signaling and peptidylprolyl cis/trans isomerase (Pin1) levels may partly explain the anti-fibrotic effects of SGLT2i in kidneys. It is important to remember that some studies have not shown any beneficial effects of SGLT2i on kidney fibrosis. Given this background, in the current review, we have summarized the studies and pathophysiologic aspects of SGL2 inhibition on renal fibrosis in various CKD models and tried to explain the potential reasons for contrasting findings.

Secondary diabetes mellitus due to primary aldosteronism

Primary aldosteronism (PA) and diabetes mellitus (DM) are clinical conditions that increase cardiovascular risk. Approximately one in five patients with PA have DM. Nevertheless, the pathophysiology linking these two entities is not entirely understood. In addition, the majority of patients with PA have glucocorticoid co-secretion, which is associated with increased risk of impaired glucose homeostasis. In the present review, we aim to comprehensively discuss all the available research data concerning the interplay between mineralocorticoid excess and glucose metabolism, with separate analysis of the sequalae in muscle, adipose tissue, liver and pancreas. Aldosterone binds both mineralocorticoid and glucocorticoid receptors and amplifies tissue glucocorticoid activity, via 11-β-hydroxysteroid dehydrogenase type 1 stimulation. A clear classification of the molecular events as per specific receptor in insulin-sensitive tissues is impossible, while their synergistic interaction is plausible. Furthermore, aldosterone induces oxidative stress and inflammation, perturbs adipokine expression, thermogenesis and lipogenesis in adipose tissue, and increases hepatic steatosis. In pancreas, enhanced oxidative stress and inflammation of beta cells, predominantly upon glucocorticoid receptor activation, impair insulin secretion. No causality between hypokalemia and impaired insulin response is yet proven; in contrast, hypokalemia appears to be implicated with insulin resistance and hepatic steatosis. The superior efficacy of adrenalectomy in ameliorating glucose metabolism vs. mineralocorticoid receptor antagonists in clinical studies highlights the contribution of non-mineralocorticoid receptor-mediated mechanisms in the pathophysiologic process. The exact role of hypokalemia, the mechanisms linking mineralocorticoid excess with hepatic steatosis, and possible disease-modifying role of pioglitazone warrant further studies.

Obesity-associated cardiometabolic complications in polycystic ovary syndrome: The potential role of sodium-glucose cotransporter-2 inhibitors

Polycystic Ovary Syndrome (PCOS) is the most common endocrine disorder in reproductive-age women. PCOS is characterized by androgen excess, oligo/anovulation, and polycystic appearance of the ovaries. Women with PCOS have an increased prevalence of multiple cardiovascular risk factors such as insulin resistance, hypertension, renal injury, and obesity. Unfortunately, there is a lack of effective, evidence-based pharmacotherapeutics to target these cardiometabolic complications. Sodium-glucose cotransporter-2 (SGLT2) inhibitors provide cardiovascular protection in patients with and without type 2 diabetes mellitus. Although the exact mechanisms of how SGLT2 inhibitors confer cardiovascular protection remains unclear, numerous mechanistic hypotheses for this protection include modulation of the renin-angiotensin system and/or the sympathetic nervous system and improvement in mitochondrial function. Data from recent clinical trials and basic research show a potential role for SGLT2 inhibitors in treating obesity-associated cardiometabolic complications in PCOS. This narrative review discusses the mechanisms of the beneficial effect of SGLT2 inhibitors in cardiometabolic diseases in PCOS.

Body fluid regulation via chronic inhibition of sodium-glucose cotransporter-2 in patients with heart failure: a post hoc analysis of the CANDLE trial

BACKGROUND

In patients with chronic heart failure (CHF) and type 2 diabetes (T2D), sodium-glucose cotransporter-2 (SGLT2) inhibition improves cardiorenal outcomes, but details of the effects on distinct subsets of body fluid volume remain incomplete.

METHODS

This was a post hoc analysis of patients with CHF and T2D in the CANDLE trial (UMIN000017669), an investigator-initiated, multi-center, randomized open-label trial that compared the effect of canagliflozin (100 mg, n = 113) with glimepiride (starting dose: 0.5 mg, n = 120) on changes in N-terminal pro-brain natriuretic peptide. The estimated plasma volume (ePV, calculated with the Straus formula) and estimated extracellular volume (eEV, determined by the body surface area) were compared between treatment groups at weeks 4, 12, and 24.

RESULTS

Among 233 patients analyzed, 166 (71.2%) had an ejection fraction (EF) > 50%. Reductions in ePV and eEV were observed only in the canagliflozin group until week 12 (change from baseline at week 12, ePV; - 7.63%; 95% confidence interval [CI], - 10.71 to - 4.55%, p < 0.001, eEV; - 123.15 mL; 95% CI, - 190.38 to - 55.92 mL, p < 0.001). While ePV stopped falling after week 12, eEV continued to fall until week 24 ([change from baseline at week 24] - [change from baseline at week 12], ePV; 1.01%; 95%CI, - 2.30-4.32%, p = 0.549, eEV; - 125.15 mL; 95% CI, - 184.35 to - 65.95 mL, p < 0.001).

CONCLUSIONS

Maintenance of a modest reduction in ePV and continuous removal of eEV via chronic SGLT2 inhibition suggests that favorable body fluid regulation contributes to the cardiorenal benefits of SGLT2 inhibitors in patients with CHF, irrespective of EF.

TRIAL REGISTRATION

UMIN000017669.

Effect of sodium-glucose cotransporter-2 inhibitors on aldosterone and renin levels in diabetes mellitus type 2 patients: a systematic review and meta-analysis

The effect of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on plasma aldosterone concentration (PAC) and plasma renin activity (PRA) levels are still inconclusive. This meta-analysis aimed to demonstrate the changes in PAC and PRA levels after the use of SGLT2i in type 2 diabetes patients. A search for relevant publications was performed using PubMed/Medline, Scopus, Cochrane, and Embase databases from their inception through May 2022. Inclusion criteria were studies that contained data on crude PAC and PRA levels before and after the use of SGLT2i in adult type 2 diabetes patients. Standardized mean difference (SMD) with a 95% confidence interval (95% CI) was calculated. Data was separately analyzed by study design: randomized controlled study (RCT) and non-randomized controlled study (non-RCT). Ten studies involving 380 patients were included with two RCT and eight non-RCT. Serum PAC levels showed no significant change after the use of SGLT2i in both RCT and non-RCT. Significantly higher PRA levels were observed after the use of SGLT2i in both RCT and non-RCT with SMD of 0.40 ng/mL/hr; 95% CI (0.06, 0.74) and SMD of 0.36 ng/mL/hr; 95%CI (0.17, 0.55), respectively. Subgroup analysis found significantly higher PRA levels after the use of SGLT2i (SMD 0.45 ng/mL/hr; 95% CI (0.18, 0.71)) only in subgroups that used for three months or less. The use of SGLT2i in diabetes mellitus type 2 patients can affect PRA levels, especially during short-term use. PRA levels should be interpreted with caution in this population.

Renoprotective mechanisms of sodium-glucose co-transporter 2 (SGLT2) inhibitors against the progression of diabetic kidney disease

Sodium-glucose co-transporter 2 inhibitors (SGLT2-Is) have emerged as a promising class of antidiabetic drugs with cardioprotective and renoprotective effects in patients with type 2 diabetes (T2D). The sodium-glucose co-transporters 1 and 2 (SGLT 1 and SGLT2) located in the renal proximal tubules are responsible for glucose reabsorption from the glomerular filtrate back into the systemic circulation. Inhibition of SGLT2, which accounts for about 90% of the glucose reabsorption, leads to a significant reduction in blood glucose levels and a concomitant increase in the urinary excretion of glucose (glycosuria). Multiple mechanisms contribute to the nephroprotective effects of SGLT2-Is in T2D patients. These include: (1) Restoration of the tubuloglomerular feedback by increasing sodium delivery at macula densa, leading to afferent arteriolar constriction and reduced glomerular hyperfiltration, (2) Decreased activation of the intra-renal renin-angiotensin-aldosterone system, which also contributes to reducing glomerular hyperfiltration, (3) Increased production of ketone bodies, which serves as an alternate fuel for adenosine triphosphate production in mitochondria, which helps in attenuating inflammation, and (4) Protection against hypoxia, oxidative stress, and fibrosis. This review elaborates on the key mechanisms that underlie the nephroprotective effects and the adverse effects of SGLT2-Is in T2D patients with progressive diabetic kidney disease.

A Role for SGLT-2 Inhibitors in Treating Non-diabetic Chronic Kidney Disease

In recent years, inhibitors of the sodium-glucose co-transporter 2 (SGLT2 inhibitors) have been shown to have significant protective effects on the kidney and the cardiovascular system in patients with diabetes. This effect is also manifested in chronic kidney disease (CKD) patients and is minimally due to improved glycaemic control. Starting from these positive findings, SGLT2 inhibitors have also been tested in patients with non-diabetic CKD or heart failure with reduced ejection fraction. Recently, the DAPA-CKD trial showed a significantly lower risk of CKD progression or death from renal or cardiovascular causes in a mixed population of patients with diabetic and non-diabetic CKD receiving dapagliflozin in comparison with placebo. In patients with heart failure and reduced ejection fraction, two trials (EMPEROR-Reduced and DAPA-HF) also found a significantly lower risk of reaching the secondary renal endpoint in those treated with an SGLT2 inhibitor in comparison with placebo. This also applied to patients with CKD. Apart from their direct mechanism of action, SGLT2 inhibitors have additional effects that could be of particular interest for patients with non-diabetic CKD. Among these, SGLT2 inhibitors reduce blood pressure and serum acid uric levels and can increase hemoglobin levels. Some safety issues should be further explored in the CKD population. SGLT2 inhibitors can minimally increase potassium levels, but this has not been shown by the CREDENCE trial. They also increase magnesium and phosphate reabsorption. These effects could become more significant in patients with advanced CKD and will need monitoring when these agents are used more extensively in the CKD population. Conversely, they do not seem to increase the risk of acute kidney injury.

Effects of SGLT2 Inhibitors and GLP-1 Receptor Agonists on Renin-Angiotensin-Aldosterone System

Sodium-glucose cotransporters inhibitors (SGLT2-i) and GLP-1 receptor agonists (GLP1-RA) are glucose-lowering drugs that are proved to reduce the cardiovascular (CV) risk in type 2 diabetes mellitus (T2DM). In this process, the renin-angiotensin-aldosterone system (RAAS) is assumed to play a role. The inhibition of SGLT2 improves hyperglycemia hampering urinary reabsorption of glucose and inducing glycosuria. This "hybrid" diuretic effect, which couples natriuresis with osmotic diuresis, potentially leads to systemic RAAS activation. However, the association between SGLT2-i and systemic RAAS activation is not straightforward. Available data indicate that SGLT2-i cause plasma renin activity (PRA) increase in the early phase of treatment, while PRA and aldosterone levels remain unchanged in chronic treated patients. Furthermore, emerging studies provide evidence that SGLT2-i might have an interfering effect on aldosterone/renin ratio (ARR) in patients with T2DM, due to their diuretic and sympathoinhibition effects. The cardio- and reno-protective effects of GLP-1-RA are at least in part related to the interaction with RAAS. In particular, GLP1-RA counteract the action of angiotensin II (ANG II) inhibiting its synthesis, increasing the inactivation of its circulating form and contrasting its action on target tissue like glomerular endothelial cells and cardiomyocytes. Furthermore, GLP1-RA stimulate natriuresis inhibiting Na+/H+ exchanger NHE-3, which is conversely activated by ANG II. Moreover, GLP1 infusion acutely reduces circulating aldosterone, but this effect does not seem to be chronically maintained in patients treated with GLP1-RA. In conclusion, both SGLT2-i and GLP1-RA seem to have several effects on RAAS, though additional studies are needed to clarify this relationship.