SGLT2 Inhibition for the Prevention and Treatment of Diabetic Kidney Disease: A Review

Degree of joint risk factor control and incident chronic kidney disease among individuals with obesity

AIM

To investigate the extent to which joint risk factor control might attenuate the excess risk of chronic kidney disease (CKD) in participants with obesity.

PATIENTS AND METHODS

We included a total of 97 538 participants who were obese at baseline and matched 97 538 normal weight control participants from the UK Biobank in the analysis. The degree of joint risk factor control was assessed based on six major CKD risk factors, including blood pressure, glycated haemoglobin, low-density lipoprotein cholesterol, albuminuria, smoking and physical activity. The Cox proportional hazards models were used to estimate associations between the degree of risk factor control and risk of CKD, following participants from their baseline assessment until the occurrence of CKD, death, or the end of the follow-up period.

RESULTS

Among participants with obesity, joint risk factor control showed an association with a stepwise reduction of incident CKD risk. Each additional risk factor control corresponded to an 11% (hazard ratio: 0.89; 95% confidence interval: 0.86-0.91) reduced risk of CKD among participants with obesity, with the optimal controlling of all six risk factors associated with a 49% (hazard ratio: 0.51; 95% confidence interval: 0.43-0.61) decrease in risk of CKD. Furthermore, in individuals with obesity who jointly controlled all six risk factors, the excess risk of CKD associated with obesity was effectively neutralized compared with normal weight control subjects. Notably, the protective correlations between the degree of joint risk factor control and the incidence of CKD were more pronounced in men compared with women, in individuals with a lower healthy food score versus a higher score, and among diabetes medication users as opposed to non-users (pinteraction = 0.017, 0.033 and 0.014, respectively).

CONCLUSION

The joint risk factor control is associated with an inverse association of CKD risk in an accumulative manner among individuals with obesity. Achieving ideal control over risk factors may effectively counterbalance the excessive risk of CKD typically associated with obesity.

Advances in the Insulin-Heart Axis: Current Therapies and Future Directions

The insulin-heart axis plays a pivotal role in the pathophysiology of cardiovascular disease (CVD) in insulin-resistant states, including type 2 diabetes mellitus. Insulin resistance disrupts glucose and lipid metabolism, leading to systemic inflammation, oxidative stress, and atherogenesis, which contribute to heart failure (HF) and other CVDs. This review was conducted by systematically searching PubMed, Scopus, and Web of Science databases for peer-reviewed studies published in the past decade, focusing on therapeutic interventions targeting the insulin-heart axis. Studies were selected based on their relevance to insulin resistance, cardiovascular outcomes, and the efficacy of pharmacologic treatments. Key findings from the review highlight the efficacy of lifestyle modifications, such as dietary changes and physical activity, which remain the cornerstone of managing insulin resistance and improving cardiovascular outcomes. Moreover, pharmacologic interventions, such as metformin, sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and dipeptidyl peptidase-4 inhibitors, have shown efficacy in reducing cardiovascular risk by addressing metabolic dysfunction, reducing inflammation, and improving endothelial function. Furthermore, emerging treatments, such as angiotensin receptor-neprilysin inhibitors, and mechanical interventions like ventricular assist devices offer new avenues for managing HF in insulin-resistant patients. The potential of these therapies to improve left ventricular ejection fraction and reverse pathological cardiac remodeling highlights the importance of early intervention. However, challenges remain in optimizing treatment regimens and understanding the long-term cardiovascular effects of these agents. Future research should focus on personalized approaches that integrate lifestyle and pharmacologic therapies to effectively target the insulin-heart axis and mitigate the burden of cardiovascular complications in insulin-resistant populations.

Amelioration of propionic acid-induced autism spectrum disorder in rats through dapagliflozin: The role of IGF-1/IGFBP-3 and the Nrf2 antioxidant pathway

The biological effects of dapagliflozin, a sodium-glucose cotransporter-2 (SGLT2) inhibitor, reveal its antioxidant and anti-inflammatory properties, suggesting therapeutic benefits beyond glycemic control. This study explores the neuroprotective effects of dapagliflozin in a rat model of autism spectrum disorder (ASD) induced by propionic acid (PPA), characterized by social interaction deficits, communication challenges, repetitive behaviors, cognitive impairments, and oxidative stress. Our research aims to find effective treatments for ASD, a condition with limited therapeutic options and significant impacts on individuals and families. PPA induces ASD-like symptoms in rodents, mimicking biochemical and behavioral features of human ASD. This study explores dapagliflozin's potential to mitigate these symptoms, providing insights into novel therapeutic avenues. The findings demonstrate that dapagliflozin enhances the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant pathway and increases levels of neurotrophic and growth factors such as brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), and insulin-like growth factor-binding protein-3 (IGFBP-3). Additionally, dapagliflozin reduces pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin-17 (IL-17), and decreases the oxidative stress marker malondialdehyde (MDA). Dapagliflozin's antioxidant properties support cognitive functions by modulating apoptotic mechanisms and enhancing antioxidant capacity. These combined effects contribute to reducing learning and memory impairments in PPA-induced ASD, highlighting dapagliflozin's potential as an adjunctive therapy for oxidative stress and inflammation-related cognitive decline in ASD. This study underscores the importance of exploring new therapeutic strategies targeting molecular pathways involved in the pathophysiology of ASD, potentially improving the quality of life for individuals affected by this disorder.

SGLT2 Inhibitors and How They Work Beyond the Glucosuric Effect. State of the Art

Type 2 diabetes mellitus (T2DM) is associated with a heightened risk of cardiovascular and renal complications. While glycemic control remains essential, newer therapeutic options, such as SGLT2 inhibitors, offer additional benefits beyond glucose reduction. This review delves into the mechanisms underlying the cardio-renal protective effects of SGLT2 inhibitors. By inducing relative hypoglycemia, these agents promote ketogenesis, optimize myocardial energy metabolism, and reduce lipotoxicity. Additionally, SGLT2 inhibitors exert renoprotective actions by enhancing renal perfusion, attenuating inflammation, and improving iron metabolism. These pleiotropic effects, including modulation of blood pressure, reduction of uric acid, and improved endothelial function, collectively contribute to the cardiovascular and renal benefits observed with SGLT2 inhibitor therapy. This review will provide clinicians with essential knowledge, understanding, and a clear recollection of this pharmacological group's mechanism of action.

Dapagliflozin restores autophagy and attenuates apoptosis via the AMPK/mTOR pathway in diabetic nephropathy rats and high glucose-induced HK-2 cells

PURPOSE

Diabetic nephropathy (DN) is a serious microvascular complication of diabetes mellitus. Significantly reduced levels of autophagy in diabetic kidneys play an important role in the development of DN. The present study investigated the effects of dapagliflozin (DAP) on renal autophagy and AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway in vivo and in vitro.

METHODS

We explored the effect of DAP in streptozotocin (STZ)-induced DN rats. The anti-DN effect of DAP was assessed by body weight, kidney weight/body weight ratio, blood and urine biochemical parameters, and pathological changes of kidney tissue. Number of autophagosomes in the kidney was investigated through Transmission electron microscopy. Besides, cell viability and apoptosis of DAP alone or combined with Compound C (CC, a selective AMPK inhibitor)-treated high glucose (HG)-induced HK-2 cells were detected by Cell Counting Kit-8 (CCK-8) and flow cytometry assays. Immunohistochemistry, Western blot, Enzyme-linked immunosorbent assay (ELISA), and immunofluorescence were employed to detect the expression levels of extracellular matrix (ECM) deposition, autophagy, apoptosis, and AMPK/mTOR pathway-associated targets in vivo and in vitro.

RESULTS

The results showed that DAP ameliorated the body weight and decreased kidney weight, fasting blood glucose, and serum/urine biochemical parameters of renal damage, as well as renal pathological changes. Moreover, DAP significantly ameliorated HG-induced cell apoptosis and ECM deposition in HK-2 cells. However, these favorable effects of DAP could be abolished by co-treatment with CC in HG-induced HK-2 cells. Mechanistically, DAP can enhance autophagy in DN including increased LC3-II/I ratio, Beclin-1, p-AMPK protein levels, and decreased p62 and p-mTOR protein expressions, as well as inhibited renal fibrosis and apoptosis.

CONCLUSION

In summary, DAP alleviated fibrosis, apoptosis, and autophagy in DN rats and HG-induced HK-2 cells by regulating the AMPK/mTOR pathway.

Hypertension in diabetes

Diabetes mellitus, a disease that affects hundreds of millions of people worldwide, is increasing in prevalence in all age groups, including children and adolescents. Much of the morbidity and mortality associated with diabetes is closely related to hypertension, often coincident with diabetes. Comorbid hypertension and diabetes often worsen the outcomes of each other, likely rooted in some overlapping pathogenic mechanisms. In this educational review, we will discuss the shared pathophysiology of diabetes and hypertension, particularly in regard to inflammation and oxidative stress, the sympathetic nervous system, vascular remodeling, and the renin-angiotensin-aldosterone system (RAAS). We will also review current hypertension diagnosis and management guidelines from many international jurisdictions for both adult and paediatric populations in the setting of diabetes. Many of these guidelines highlight the use and utility of RAAS blockers in this clinical scenario; however, on review of the evidence for their use, several meta-analyses and systematic reviews fail to demonstrate superiority of RAAS blockers over other anti-hypertensive medications. Finally, we discuss several new anti-hypertensive medications, review their mechanisms of action, and highlight some of the evidence for their use in the setting of hypertension and diabetes.

The redox-sensitive GSK3β is a key regulator of glomerular podocyte injury in type 2 diabetic kidney disease

Emerging evidence suggests that GSK3β, a redox-sensitive transducer downstream of insulin signaling, acts as a convergent point for myriad pathways implicated in kidney injury, repair, and regeneration. However, its role in diabetic kidney disease remains controversial. In cultured glomerular podocytes, exposure to a milieu of type 2 diabetes elicited prominent signs of podocyte injury and degeneration, marked by loss of homeostatic marker proteins like synaptopodin, actin cytoskeleton disruption, oxidative stress, apoptosis, and stress-induced premature senescence, as shown by increased staining for senescence-associated β-galactosidase activity, amplified formation of γH2AX foci, and elevated expression of mediators of senescence signaling, like p21 and p16INK4A. These degenerative changes coincided with GSK3β hyperactivity, as evidenced by GSK3β overexpression and reduced inhibitory phosphorylation of GSK3β, and were averted by tideglusib, a highly-selective small molecule inhibitor of GSK3β. In agreement, post-hoc analysis of a publicly-available glomerular transcriptomics dataset from patients with type 2 diabetic nephropathy revealed that the curated diabetic nephropathy-related gene set was enriched in high GSK3β expression group. Mechanistically, GSK3β-modulated nuclear factor Nrf2 signaling is involved in diabetic podocytopathy, because GSK3β knockdown reinforced Nrf2 antioxidant response and suppressed oxidative stress, resulting in an improvement in podocyte injury and senescence. Conversely, ectopic expression of the constitutively active mutant of GSK3β impaired Nrf2 antioxidant response and augmented oxidative stress, culminating in an exacerbated diabetic podocyte injury and senescence. Moreover, IRS-1 was found to be a cognate substrate of GSK3β for phosphorylation at IRS-1S332, which negatively regulates IRS-1 activity. GSK3β hyperactivity promoted IRS-1 phosphorylation, denoting a desensitized insulin signaling. Consistently, in vivo in db/db mice with diabetic nephropathy, GSK3β was hyperactive in glomerular podocytes, associated with IRS-1 hyperphosphorylation, impaired Nrf2 response and premature senescence. Our finding suggests that GSK3β is likely a novel therapeutic target for treating type 2 diabetic glomerular injury.

Genetic or pharmacologic blockade of mPGES-2 attenuates renal lipotoxicity and diabetic kidney disease by targeting Rev-Erbα/FABP5 signaling

Diabetic kidney disease (DKD) is one of the most common complications of diabetes, and no specific drugs are clinically available. We have previously demonstrated that inhibiting microsomal prostaglandin E synthase-2 (mPGES-2) alleviated type 2 diabetes by enhancing β cell function and promoting insulin production. However, the involvement of mPGES-2 in DKD remains unclear. Here, we aimed to analyze the association of enhanced mPGES-2 expression with impaired metabolic homeostasis of renal lipids and subsequent renal damage. Notably, global knockout or pharmacological blockage of mPGES-2 attenuated diabetic podocyte injury and tubulointerstitial fibrosis, thereby ameliorating lipid accumulation and lipotoxicity. These findings were further confirmed in podocyte- or tubule-specific mPGES-2-deficient mice. Mechanistically, mPGES-2 and Rev-Erbα competed for heme binding to regulate fatty acid binding protein 5 expression and lipid metabolism in the diabetic kidney. Our findings suggest a potential strategy for treating DKD via mPGES-2 inhibition.

Endothelial dysfunction in vascular complications of diabetes: a comprehensive review of mechanisms and implications

Diabetic vascular complications are prevalent and severe among diabetic patients, profoundly affecting both their quality of life and long-term prospects. These complications can be classified into macrovascular and microvascular complications. Under the impact of risk factors such as elevated blood glucose, blood pressure, and cholesterol lipids, the vascular endothelium undergoes endothelial dysfunction, characterized by increased inflammation and oxidative stress, decreased NO biosynthesis, endothelial-mesenchymal transition, senescence, and even cell death. These processes will ultimately lead to macrovascular and microvascular diseases, with macrovascular diseases mainly characterized by atherosclerosis (AS) and microvascular diseases mainly characterized by thickening of the basement membrane. It further indicates a primary contributor to the elevated morbidity and mortality observed in individuals with diabetes. In this review, we will delve into the intricate mechanisms that drive endothelial dysfunction during diabetes progression and its associated vascular complications. Furthermore, we will outline various pharmacotherapies targeting diabetic endothelial dysfunction in the hope of accelerating effective therapeutic drug discovery for early control of diabetes and its vascular complications.

Canagliflozin regulates metabolic reprogramming in diabetic kidney disease by inducing fasting-like and aestivation-like metabolic patterns

AIMS/HYPOTHESIS

Sodium-glucose co-transporter 2 (SGLT2) inhibitors (SGLT2i) are antihyperglycaemic drugs that protect the kidneys of individuals with type 2 diabetes mellitus. However, the underlying mechanisms mediating the renal benefits of SGLT2i are not fully understood. Considering the fuel switches that occur during therapeutic SGLT2 inhibition, we hypothesised that SGLT2i induce fasting-like and aestivation-like metabolic patterns, both of which contribute to the regulation of metabolic reprogramming in diabetic kidney disease (DKD).

METHODS

Untargeted and targeted metabolomics assays were performed on plasma samples from participants with type 2 diabetes and kidney disease (n=35, 11 women) receiving canagliflozin (CANA) 100 mg/day at baseline and 12 week follow-up. Next, a systematic snapshot of the effect of CANA on key metabolites and pathways in the kidney was obtained using db/db mice. Moreover, the effects of glycine supplementation in db/db mice and human proximal tubular epithelial cells (human kidney-2 [HK-2]) cells were studied.

RESULTS

Treatment of DKD patients with CANA for 12 weeks significantly reduced HbA1c from a median (interquartile range 25-75%) of 49.0 (44.0-57.0) mmol/mol (7.9%, [7.10-9.20%]) to 42.2 (39.7-47.7) mmol/mol (6.8%, [6.40-7.70%]), and reduced urinary albumin/creatinine ratio from 67.8 (45.9-159.0) mg/mmol to 47.0 (26.0-93.6) mg/mmol. The untargeted metabolomics assay showed downregulated glycolysis and upregulated fatty acid oxidation. The targeted metabolomics assay revealed significant upregulation of glycine. The kidneys of db/db mice undergo significant metabolic reprogramming, with changes in sugar, lipid and amino acid metabolism; CANA regulated the metabolic reprogramming in the kidneys of db/db mice. In particular, the pathways for glycine, serine and threonine metabolism, as well as the metabolite of glycine, were significantly upregulated in CANA-treated kidneys. Glycine supplementation ameliorated renal lesions in db/db mice by inhibiting food intake, improving insulin sensitivity and reducing blood glucose levels. Glycine supplementation improved apoptosis of human proximal tubule cells via the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway.

CONCLUSIONS/INTERPRETATION

In conclusion, our study shows that CANA ameliorates DKD by inducing fasting-like and aestivation-like metabolic patterns. Furthermore, DKD was ameliorated by glycine supplementation, and the beneficial effects of glycine were probably due to the activation of the AMPK/mTOR pathway.

The times they are K+-changin': bringing the potassium curriculum out of the 20th century

PURPOSE OF REVIEW

Although most of the current medical education literature has focused on teaching strategies, little attention has been devoted to selecting appropriate course content. Despite elegant descriptions of physiologic mechanisms in recent decades, medical school curricula and students continue to rely on outdated textbooks and certification examination study aids composed to fit an antiquated exam blueprint.

RECENT FINDINGS

Advances in our understanding of potassium physiology offer multiple examples of key concepts that deserve to be included in the modern-day renal physiology curriculum, including the relationship of potassium to blood pressure and the potassium 'switch', the aldosterone paradox, and novel pharmacologic agents that target dietary potassium absorption and potassium handling in the kidney.

SUMMARY

Key advances in our understanding and application of renal physiology to patient care have not been readily integrated into the nephrology curriculum of medical students. Difficult questions remain regarding when new concepts are sufficiently established to be introduced to medical students in the preclinical years.

Peter WL, Shubrook JH. Type 2 Diabetes and Chronic Kidney Disease: An Opportunity for Pharmacists to Improve Outcomes

Chronic kidney disease (CKD) is an important contributor to end-stage kidney disease, cardiovascular disease, and death in people with type 2 diabetes (T2D), but current evidence suggests that diagnosis and treatment are often not optimized. This review examines gaps in care for patients with CKD and how pharmacist interventions can mitigate these gaps. We conducted a PubMed search for published articles reporting on real-world CKD management practice and compared the findings with current recommendations. We find that adherence to guidelines on screening for CKD in patients with T2D is poor with particularly low rates of testing for albuminuria. When CKD is diagnosed, the prescription of recommended heart-kidney protective therapies is underutilized, possibly due to issues around treatment complexity and safety concerns. Cost and access are barriers to the prescription of newer therapies and treatment is dependent on racial, ethnic, and socioeconomic factors. Rates of nephrologist referrals for difficult cases are low in part due to limitations of information and communication between specialties. We believe that pharmacists can play a vital role in improving outcomes for patients with CKD and T2D and support the cost-effective use of healthcare resources through the provision of comprehensive medication management as part of a multidisciplinary team. The Advancing Kidney Health through Optimal Medication Management initiative supports the involvement of pharmacists across healthcare systems to ensure that comprehensive medication management can be optimally implemented.

Exploring the Therapeutic Significance of microRNAs and lncRNAs in Kidney Diseases

MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two crucial classes of transcripts that belong to the major group of non-coding RNAs (ncRNAs). These RNA molecules have significant influence over diverse molecular processes due to their crucial role as regulators of gene expression. However, the dysregulated expression of these ncRNAs constitutes a fundamental factor in the etiology and progression of a wide variety of multifaceted human diseases, including kidney diseases. In this context, over the past years, compelling evidence has shown that miRNAs and lncRNAs could be prospective targets for the development of next-generation drugs against kidney diseases as they participate in a number of disease-associated processes, such as podocyte and nephron death, renal fibrosis, inflammation, transition from acute kidney injury to chronic kidney disease, renal vascular changes, sepsis, pyroptosis, and apoptosis. Hence, in this current review, we critically analyze the recent findings concerning the therapeutic inferences of miRNAs and lncRNAs in the pathophysiological context of kidney diseases. Additionally, with the aim of driving advances in the formulation of ncRNA-based drugs tailored for the management of kidney diseases, we discuss some of the key challenges and future prospects that should be addressed in forthcoming investigations.

Evidential support for garlic supplements against diabetic kidney disease: a preclinical meta-analysis and systematic review

Garlic (Allium sativum L.) is a popular spice that is widely used for food and medicinal purposes and has shown potential effects on diabetic kidney disease (DKD). Nevertheless, systematic preclinical studies are still lacking. In this meta-analysis and systematic review, we evaluated the role and potential mechanisms of action of garlic and its derived components in animal models of DKD. We searched eight databases for relevant studies from the establishment of the databases to December 2022 and updated in April 2023 before the completion of this review. A total of 24 trials were included in the meta-analysis. It provided preliminary evidence that supplementing with garlic could improve the indicators of renal function (BUN, Scr, 24 h urine volume, proteinuria, and KI) and metabolic disorders (BG, insulin, and body weight). Meanwhile, the beneficial effects of garlic and its components in DKD could be related to alleviating oxidative stress, suppressing inflammatory reactions, delaying renal fibrosis, and improving glucose metabolism. Furthermore, time-dose interval analysis exhibited relatively greater effectiveness when garlic products were supplied at doses of 500 mg kg-1 with interventions lasting 8-10 weeks, and garlic components were administered at doses of 45-150 mg kg-1 with interventions lasting 4-10 weeks. This meta-analysis and systematic review highlights for the first time the therapeutic potential of garlic supplementation in animal models of DKD and offers a more thorough evaluation of its effects and mechanisms to establish an evidence-based basis for designing future clinical trials.

Fatty acids and inflammatory stimuli induce expression of long-chain acyl-CoA synthetase 1 to promote lipid remodeling in diabetic kidney disease

Fatty acid handling and complex lipid synthesis are altered in the kidney cortex of diabetic patients. We recently showed that inhibition of the renin-angiotensin system without changes in glycemia can reverse diabetic kidney disease (DKD) and restore the lipid metabolic network in the kidney cortex of diabetic (db/db) mice, raising the possibility that lipid remodeling may play a central role in DKD. However, the roles of specific enzymes involved in lipid remodeling in DKD have not been elucidated. In the present study, we used this diabetic mouse model and a proximal tubule epithelial cell line (HK2) to investigate the potential relationship between long-chain acyl-CoA synthetase 1 (ACSL1) and lipid metabolism in response to fatty acid exposure and inflammatory signals. We found ACSL1 expression was significantly increased in the kidney cortex of db/db mice, and exposure to palmitate or tumor necrosis factor-α significantly increased Acsl1 mRNA expression in HK-2 cells. In addition, palmitate treatment significantly increased the levels of long-chain acylcarnitines and fatty acyl CoAs in HK2 cells, and these increases were abolished in HK2 cell lines with specific deletion of Acsl1(Acsl1KO cells), suggesting a key role for ACSL1 in fatty acid β-oxidation. In contrast, tumor necrosis factor-α treatment significantly increased the levels of short-chain acylcarnitines and long-chain fatty acyl CoAs in HK2 cells but not in Acsl1KO cells, consistent with fatty acid channeling to complex lipids. Taken together, our data demonstrate a key role for ACSL1 in regulating lipid metabolism, fatty acid partitioning, and inflammation.

Empagliflozin treatment of cardiotoxicity: A comprehensive review of clinical, immunobiological, neuroimmune, and therapeutic implications

Cancer and cardiovascular disorders are known as the two main leading causes of mortality worldwide. Cardiotoxicity is a critical and common adverse effect of cancer-related chemotherapy. Chemotherapy-induced cardiotoxicity has been associated with various cancer treatments, such as anthracyclines, immune checkpoint inhibitors, and kinase inhibitors. Different methods have been reported for the management of chemotherapy-induced cardiotoxicity. In this regard, sodium-glucose cotransporter-2 inhibitors (SGLT2i), a class of antidiabetic agents, have recently been applied to manage heart failure patients. Further, SGLT2i drugs such as EMPA exert protective cardiac and systemic effects. Moreover, it can reduce inflammation through the mediation of major inflammatory components, such as Nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasomes, Adenosine 5'-monophosphate-activated protein kinase (AMPK), and c-Jun N-terminal kinase (JNK) pathways, Signal transducer and activator of transcription (STAT), and overall decreasing transcription of proinflammatory cytokines. The clinical outcome of EMPA administration is related to improving cardiovascular risk factors, including body weight, lipid profile, blood pressure, and arterial stiffness. Intriguingly, SGLT2 suppressors can regulate microglia-driven hyperinflammation affecting neurological and cardiovascular disorders. In this review, we discuss the protective effects of EMPA in chemotherapy-induced cardiotoxicity from molecular, immunological, and neuroimmunological aspects to preclinical and clinical outcomes.

Dapagliflozin alleviates renal inflammation and protects against diabetic kidney diseases, both dependent and independent of blood glucose levels

Introduction

Diabetic kidney disease (DKD) has become the leading cause of end-stage renal disease worldwide. Therefore, efforts to understand DKD pathophysiology and prevent its development at the early phase are highly warranted.

Methods

Here, we analyzed kidneys from healthy mice, diabetic mice, and diabetic mice treated with the sodium-glucose cotransporter 2 inhibitor dapagliflozin using ATAC and RNA sequencing. The findings were verified at the protein levels and in cultured cells.

Results

Our combined method of ATAC and RNA sequencing revealed Csf2rb, Btla, and Isg15 as the key candidate genes associated with hyperglycemia, azotemia, and albuminuria. Their protein levels were altered together with multiple other inflammatory cytokines in the diabetic kidney, which was alleviated by dapagliflozin treatment. Cell culture of immortalized renal tubular cells and macrophages unraveled that dapagliflozin could directly effect on these cells in vitro as an anti-inflammatory agent independent of glucose concentrations. We further proved that dapagliflozin attenuated ischemia/reperfusion-induced chronic kidney injury and renal inflammation in mice.

Discussion

Overall, our data emphasize the importance of inflammatory factors to the pathogenesis of DKD, and provide valuable mechanistic insights into the renoprotective role of dapagliflozin.

Role of MCP-1/CCR2 axis in renal fibrosis: Mechanisms and therapeutic targeting

Renal fibrosis is a common pathological manifestation in various chronic kidney diseases. Inflammation plays a central role in renal fibrosis development. Owing to their significant participation in inflammation and autoimmunity, chemokines have always been the hot spot and focus of scientific research and clinical intervention. Among the chemokines, monocyte chemoattractant protein-1 (MCP-1), also known as C-C motif chemokine ligand 2, together with its main receptor C-C chemokine receptor type 2 (CCR2) are important chemokines in renal fibrosis. The MCP-1/CCR2 axis is activated when MCP-1 binds to CCR2. Activation of MCP-1/CCR2 axis can induce chemotaxis and activation of inflammatory cells, and initiate a series of signaling cascades in renal fibrosis. It mediates and promotes renal fibrosis by recruiting monocyte, promoting the activation and transdifferentiation of macrophages. This review summarizes the complex physical processes of MCP-1/CCR2 axis in renal fibrosis and addresses its general mechanism in renal fibrosis by using specific examples, together with the progress of targeting MCP-1/CCR2 in renal fibrosis with a view to providing a new direction for renal fibrosis treatment.

Multifaceted relationship between diabetes and kidney diseases: Beyond diabetes

Diabetes mellitus is one of the most common causes of chronic kidney disease. Kidney involvement in patients with diabetes has a wide spectrum of clinical presentations ranging from asymptomatic to overt proteinuria and kidney failure. The development of kidney disease in diabetes is associated with structural changes in multiple kidney compartments, such as the vascular system and glomeruli. Glomerular alterations include thickening of the glomerular basement membrane, loss of podocytes, and segmental mesangiolysis, which may lead to microaneurysms and the development of pathognomonic Kimmelstiel-Wilson nodules. Beyond lesions directly related to diabetes, awareness of the possible coexistence of nondiabetic kidney disease in patients with diabetes is increasing. These nondiabetic lesions include focal segmental glomerulosclerosis, IgA nephropathy, and other primary or secondary renal disorders. Differential diagnosis of these conditions is crucial in guiding clinical management and therapeutic approaches. However, the relationship between diabetes and the kidney is bidirectional; thus, new-onset diabetes may also occur as a complication of the treatment in patients with renal diseases. Here, we review the complex and multifaceted correlation between diabetes and kidney diseases and discuss clinical presentation and course, differential diagnosis, and therapeutic oppor-tunities offered by novel drugs.

Impact of sodium-glucose cotransporter-2 inhibitors on kidney outcomes in type 2 diabetes: A tertiary center experience

BACKGROUND

Diabetic nephropathy (DN) is a complication of chronic hyperglycemia associated with diabetes mellitus (DM). Several studies have demonstrated the positive impact of sodium-glucose cotransporter-2 (SGLT2) inhibitors on kidney outcomes. The objective of the study was to evaluate the effects of dapagliflozin, an SGLT2 inhibitor, on kidney outcomes in Saudi patients with type 2 DM.

MATERIALS AND METHODS

Study included all Saudi patients with type 2 DM who visited our center from August 1, 2021, to July 31, 2022, and had been on dapagliflozin for at least 3 months. Data was abstracted through chart review for all patients included in the study. Paired t-test or Wilcoxon signed-rank test were used to compare the results before and after treatment for continuous variables and the McNemar test was used to compare the results for categorical data.

RESULTS

Study included 184 Saudi patients with type 2 diabetes with a mean age of 61.32 years (SD=9.37). Dapagliflozin 10 mg/day significantly reduced hemoglobin A1C (HbA1C) from a mean (SD) of 9.00 to 8.40 (P < 0.001). Among a subgroup of patients with significant proteinuria (n = 83), dapagliflozin significantly reduced ACR from a median of 93.1 to 64.9 mg/g (P = 0.001). Following treatment, the estimated glomerular filtration rate improved from a mean of 69.83 to 71.68 mL/min and the mean arterial pressure (MAP) fell from 90.03 to 89.06 mmHg, both were not statistically significant. Despite a statistically insignificant increase in the episodes of urinary tract infections (UTIs), the hospitalization rate declined. No episodes of amputations or ketoacidosis occurred during the study period.

CONCLUSION

SGLT2 inhibitors had beneficial effects among Saudi patients with type 2 diabetes by improving diabetic control and lowering proteinuria. Dapagliflozin did not result in significant harm, including UTIs, amputations, and ketoacidosis.

Irisin ameliorates diabetic kidney disease by restoring autophagy in podocytes

Many studies have highlighted the importance of moderate exercise. While it can attenuate diabetic kidney disease, its mechanism has remained unclear. The level of myokine irisin in plasma increases during exercise. We found that irisin was decreased in diabetic patients and was closely related to renal function, proteinuria, and podocyte autophagy injury. Muscle-specific overexpression of PGC-1α (mPGC-1α) in a mouse model is known to increase plasma irisin levels. The mPGC-1α mice were crossed with db/m mice to obtain db/db mPGC-1α+ mice in the present study. Compared to db/db mice without mPGC-1α, plasma irisin was increased, and albuminuria and glomerular pathological damage were both alleviated in db/db mPGC-1α+ mice. Impaired autophagy in podocytes was restored as well. Irisin inhibited the activation of the PI3K/AKT/mTOR signaling pathway in cultured human podocytes and improved damaged autophagy induced by high glucose levels. Then, db/db mice were treated with recombinant irisin, which had similar beneficial effects on the kidney as those in db/db mPGC-1α+ mice, with alleviated glomerular injury and albuminuria. Moreover, the autophagy in podocytes was also significantly restored. These results suggest that irisin secreted by skeletal muscles protects the kidney from diabetes mellitus damage. It also restores autophagy in podocytes by inhibiting the abnormal activation of the PI3K/AKT/mTOR signaling pathway. Thus, irisin may become a new drug for the prevention and treatment of diabetic nephropathy.

SGLT-2 inhibitors improve cardiovascular and renal outcomes in patients with CKD: a systematic review and meta-analysis

The effect of sodium-glucose co-transporter-2 (SGLT-2) inhibitors on cardiovascular and renal outcomes has not been systematically reviewed across baseline kidney function groups. We conducted a systematic review and meta-analysis of randomized control trials (RCTs) with SGLT-2 inhibitors in patients with and without CKD. We performed a PubMed/Medline search of randomized, placebo-controlled, event-driven outcome trials of SGLT-2 inhibitors versus active or placebo control in patients with and without diabetes from inception to November 2022. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73m2 (PROSPERO registration CRD4202016054). The primary outcome was cardiovascular death. Secondary outcomes included hospitalization for heart failure, major adverse cardiovascular events, CKD progression, all-cause mortality, treatment discontinuation, and acute kidney injury (AKI). The relative risk (RR) was estimated using a random-effects model. Twelve RCTs were included in this meta-analysis (89,191 patients, including 38,949 with eGFR < 60 ml/min/1.73m2). Use of an SGLT-2 inhibitor in patients with CKD was associated with a lower incidence of cardiovascular death (RR 0.87; 95% CI 0.79-0.95) and of heart failure (RR 0.67; 95% CI 0.61-0.75), compared with placebo. Heart failure risk reduction with SGLT-2 inhibitors was larger among patients with CKD compared with patients without CKD (RR for the interaction 0.87, 95% CI 0.75-1.02, and p-value for interaction 0.08). SGLT-2 inhibitors were associated with a lower incidence of CKD progression among patients with pre-existing CKD: RR 0.77 (95% CI 0.68-0.88), compared with placebo. Among patients with CKD, a lower risk of AKI (RR 0.82; 95% CI 0.72-0.93) and treatment discontinuation was seen with SGLT-2 inhibitors compared with placebo. SGLT-2 inhibitors offer substantial protection against cardiovascular and renal outcomes in patients with CKD. These results strongly advocate in favor of using them in patients with CKD and keeping them as kidney function declines.

Intravenous injection of human umbilical cord-derived mesenchymal stem cells ameliorates not only blood glucose but also nephrotic complication of diabetic rats through autophagy-mediated anti-senescent mechanism

BACKGROUND

Diabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus, which is characterized by early occurrence of albuminuria and end-stage glomerulosclerosis. Senescence and autophagy of podocytes play an important role in DN development. Human umbilical cord-derived mesenchymal stem cells (hucMSCs) have potential in the treatment of diabetes and its complications. However, the role of hucMSCs in the treatment of DN and the underlying mechanism remain unclear.

METHODS

In vivo, a streptozotocin-induced diabetic male Sprague Dawley rat model was established to determine the renoprotective effect of hucMSCs on DN by biochemical analysis, histopathology, and immunohistochemical staining of renal tissues. And the distribution of hucMSCs in various organs in rats within 168 h was analyzed. In vitro, CCK8 assay, wound healing assay, and β-galactosidase staining were conducted to detect the beneficial effects of hucMSCs on high glucose-induced rat podocytes. Real-time PCR and western blot assays were applied to explore the mechanism of action of hucMSCs.

RESULTS

The in vivo data revealed that hucMSCs were distributed into kidneys and significantly protected kidneys from diabetic damage. The in vitro data indicated that hucMSCs improved cell viability, wound healing, senescence of the high glucose-damaged rat podocytes through a paracrine action mode. Besides, the altered expressions of senescence-associated genes (p16, p53, and p21) and autophagy-associated genes (Beclin-1, p62, and LC3) were improved by hucMSCs. Mechanistically, hucMSCs protected high glucose-induced injury in rat podocytes by activating autophagy and attenuating senescence through the AMPK/mTOR pathway.

CONCLUSIONS

In conclusion, hucMSCs might be a promising therapeutic strategy for the clinical treatment of DN-induced renal damages.

Canagliflozin Ameliorates Oxidative Stress and Autistic-like Features in Valproic-Acid-Induced Autism in Rats: Comparison with Aripiprazole Action

Based on their proven anti-inflammatory and antioxidant effects, recent studies have examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitors in neurodevelopmental disorders such as autism spectrum disorder (ASD). Therefore, the aim of this study is to assess the effects of subchronic systemic treatment with intraperitoneal (i.p.) canagliflozin (20, 50, and 100 mg/kg) compared to aripiprazole (ARP) (3 mg/g, i.p.) in a valproic acid (VPA)-induced rat model of autism. The behavioral characteristics of ASD, oxidative stress, and acetylcholinesterase (AChE) activity in rats with ASD-like behaviors, which were induced by prenatal exposure to VPA, were evaluated. The behavioral assessment methods used for this study were the open field test (OFT), the marble-burying test (MBT), and the nestlet-shredding test (NST) to examine their exploratory, anxiety, and compulsiveness-like actions, while the biochemical assessment used for this study was an ELISA colorimetric assay to measure ASD biomarker activity in the hippocampus, prefrontal cortex, and cerebellum. Rats that were pretreated with 100 mg/kg of canagliflozin displayed a significantly lower percentage of shredding (1.12 ± 0.6%, p < 0.01) compared to the ARP group (3.52 ± 1.6%). Pretreatment with (20 mg/kg, 50 mg/kg, and 100 mg/kg) canagliflozin reversed anxiety levels and hyperactivity and reduced hyper-locomotor activity significantly (161 ± 34.9 s, p < 0.05; 154 ± 44.7 s, p < 0.05; 147 ± 33.6 s, p < 0.05) when compared with the VPA group (303 ± 140 s). Moreover, canagliflozin and ARP mitigated oxidative stress status by restoring levels of glutathione (GSH) and catalase (CAT) and increasing the levels of malondialdehyde (MDA) in all tested brain regions. The observed results propose repurposing of canagliflozin in the therapeutic management of ASD. However, further investigations are still required to verify the clinical relevance of canagliflozin in ASD.

Digging deep into cells to find mechanisms of kidney protection by SGLT2 inhibitors

The sodium-glucose cotransporter-2 (SGLT2) is expressed on the luminal side of proximal tubule epithelial cells in the kidney. While pharmacological inhibition of SGLT2 provides kidney protection in diabetic kidney disease (DKD), the molecular mechanisms remain unclear. In this issue of the JCI, Schaub et al. report on the changes in single-cell transcriptional profiles of young participants with type 2 diabetes who received SGLT2 inhibitors. Treatment with SGLT2 inhibitors restored metabolic perturbations in proximal tubular cells and reduced expression of the inflammatory signaling molecule mTORC1. Notably, changes in transcripts and mTORC1 were also found in the kidney of a diabetes mouse model treated with an SGLT2 inhibitor, supporting use of this model for further studies. These findings reveal cellular mechanisms of SGLT2 inhibitors and are important for advancing therapeutic targets in the treatment of DKD.

Kidney Drug Transporters in Pharmacotherapy

The kidney functions not only as a metabolite elimination organ but also plays an important role in pharmacotherapy. The kidney tubule epithelia cells express membrane carriers and transporters, which play an important role in drug elimination, and can determine drug nephrotoxicity and drug-drug interactions, as well as constituting direct drug targets. The above aspects of kidney transport proteins are discussed in the review.

Bibliometric Analysis and Visualization of Research Progress in the Diabetic Nephropathy Field from 2001 to 2021

Methods

The PubMed database was searched to identify all studies related to DN that were published from 2001 to 2021, with these studies being separated into four time-based groups. The characteristics of these studies were analyzed and extracted using BICOMB. Biclustering analyses for each of these groups were then performed using gCLUTO, with these results then being analyzed and GraphPad Prism 5 being used to construct strategy diagrams. The social network analyses (SNAs) for each group of studies were conducted using NetDraw and UCINET.

Results

In total, 18,889 DN-associated studies published from 2001 to 2021 and included in the PubMed database were incorporated into the present bibliometric analysis. Biclustering analysis and strategy diagrams revealed that active areas of research interest in the DN field include studies of the drug-based treatment, diagnosis, etiology, pathology, physiopathology, and epidemiology of DN. The specific research topics associated with these individual areas, however, have evolved over time in a dynamic manner. Strategy diagrams and SNA results revealed podocyte metabolism as an emerging research hotspot in the DN research field from 2010 to 2015, while DN-related microRNAs, signal transduction, and mesangial cell metabolism have emerged as more recent research hotspots in the interval from 2016 to 2021.

Conclusion

Through analyses of PubMed-indexed studies pertaining to DN published since 2001, the results of this bibliometric analysis offer a knowledge framework and insight into active and historical research hotspots in the DN research space, enabling investigators to readily understand the dynamic evolution of this field over the past two decades. Importantly, these analyses also enable the prediction of future DN-related research hotspots, thereby potentially guiding more focused and impactful research efforts.

Guanylyl cyclase/natriuretic peptide receptor-A: Identification, molecular characterization, and physiological genomics

The natriuretic peptides (NPs) hormone family, which consists mainly of atrial, brain, and C-type NPs (ANP, BNP, and CNP), play diverse roles in mammalian species, ranging from renal, cardiac, endocrine, neural, and vascular hemodynamics to metabolic regulations, immune responsiveness, and energy distributions. Over the last four decades, new data has transpired regarding the biochemical and molecular compositions, signaling mechanisms, and physiological and pathophysiological functions of NPs and their receptors. NPs are incremented mainly in eliciting natriuretic, diuretic, endocrine, vasodilatory, and neurological activities, along with antiproliferative, antimitogenic, antiinflammatory, and antifibrotic responses. The main locus responsible in the biological and physiological regulatory actions of NPs (ANP and BNP) is the plasma membrane guanylyl cyclase/natriuretic peptide receptor-A (GC-A/NPRA), a member of the growing multi-limbed GC family of receptors. Advances in this field have provided tremendous insights into the critical role of Npr1 (encoding GC-A/NPRA) in the reduction of fluid volume and blood pressure homeostasis, protection against renal and cardiac remodeling, and moderation and mediation of neurological disorders. The generation and use of genetically engineered animals, including gene-targeted (gene-knockout and gene-duplication) and transgenic mutant mouse models has revealed and clarified the varied roles and pleiotropic functions of GC-A/NPRA in vivo in intact animals. This review provides a chronological development of the biochemical, molecular, physiological, and pathophysiological functions of GC-A/NPRA, including signaling pathways, genomics, and gene regulation in both normal and disease states.

Sodium glucose co-transporter 2 (SGLT2) inhibition via dapagliflozin improves diabetic kidney disease (DKD) over time associatied with increasing effect on the gut microbiota in db/db mice

BACKGROUND

The intestinal microbiota disorder gradually aggravates during the progression of diabetes. Dapagliflozin (DAPA) can improve diabetes and diabetic kidney disease(DKD). However, whether the gut microbiota plays a role in the protection of DAPA for DKD remains unclear.

METHODS

To investigate the effects of DAPA on DKD and gut microbiota composition during disease progression, in our study, we performed 16S rRNA gene sequencing on fecal samples from db/m mice (control group), db/db mice (DKD model group), and those treated with DAPA (treat group) at three timepoints of 14weeks\18weeks\22weeks.

RESULTS

We found that DAPA remarkably prevented weight loss and lowered fasting blood glucose in db/db mice during disease progression, eventually delaying the progression of DKD. Intriguingly, the study strongly suggested that there is gradually aggravated dysbacteriosis and increased bile acid during the development of DKD. More importantly, comparisons of relative abundance at the phylum level and partial least squares-discriminant analysis (PLS-DA) plots roughly reflected that the effect of DAPA on modulating the flora of db/db mice increased with time. Specifically, the relative abundance of the dominant Firmicutes and Bacteroidetes was not meaningfully changed among groups at 14 weeks as previous studies described. Interestingly, they were gradually altered in the treat group compared to the model group with a more protracted intervention of 18 weeks and 22 weeks. Furthermore, the decrease of Lactobacillus and the increase of norank_f:Muribaculaceae could account for the differences at the phylum level observed between the treat group and the model group at 18 weeks and 22 weeks.

CONCLUSION

We firstly found that the protective effect of DAPA on DKD may be related to the dynamic improvement of the gut microbiota over time, possibly associated with the impact of DAPA on the bile acid pool and its antioxidation effect.

Mechanistic Study of Schisandra chinensis Fruit Mixture Based on Network Pharmacology, Molecular Docking and Experimental Validation to Improve the Inflammatory Response of DKD Through AGEs/RAGE Signaling Pathway

Background

Diabetic kidney disease (DKD) is a major cause of end-stage renal disease (ESRD), and inflammation is the main causative mechanism. Schisandra chinensis fruit Mixture (SM) is an herbal formulation that has been used for a long time to treat DKD. However, its pharmacological and molecular mechanisms have not been clearly elucidated. The aim of this study was to investigate the potential mechanisms of SM for the treatment of DKD through network pharmacology, molecular docking and experimental validation.

Methods

The chemical components in SM were comprehensively identified and collected using liquid chromatography-tandem mass spectrometry (LC-MS) and database mining. The mechanisms were investigated using a network pharmacology, including obtaining SM-DKD intersection targets, completing protein-protein interactions (PPI) by Cytoscape to obtain key potential targets, and then revealing potential mechanisms of SM for DKD by GO and KEGG pathway enrichment analysis. The important pathways and phenotypes screened by the network analysis were validated experimentally in vivo. Finally, the core active ingredients were screened by molecular docking.

Results

A total of 53 active ingredients of SM were retrieved by database and LC-MS, and 143 common targets of DKD and SM were identified; KEGG and PPI showed that SM most likely exerted anti-DKD effects by regulating the expression of AGEs/RAGE signaling pathway-related inflammatory factors. In addition, our experimental validation results showed that SM improved renal function and pathological changes in DKD rats, down-regulated AGEs/RAGE signaling pathway, and further down-regulated the expression of TNF-α, IL-1β, IL-6, and up-regulated IL-10. Molecular docking confirmed the tight binding properties between (+)-aristolone, a core component of SM, and key targets.

Conclusion

This study reveals that SM improves the inflammatory response of DKD through AGEs/RAGE signaling pathway, thus providing a novel idea for the clinical treatment of DKD.

Comparison the effects of finerenone and SGLT2i on cardiovascular and renal outcomes in patients with type 2 diabetes mellitus: A network meta-analysis

Background

Finerenone and sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been shown to improve cardiovascular and renal outcomes in patients with type 2 diabetes mellitus (T2DM), while the relative efficacy has not been determined.

Methods

The databases of PubMed, Embase and Cochrane were searched for relevant cardiovascular or renal outcome trials of SGLT2i or finerenone. The end points were major adverse cardiovascular events (MACE), nonfatal stroke (NS), myocardial infarction (MI), hospitalization for heart failure (HHF), cardiovascular death (CVD), and renal composite outcome (RCO). Network meta-analysis was performed using Bayesian networks to obtain pooled hazard ratios (HR) and 95% confidence intervals (CI). The probability values for ranking active and placebo interventions were calculated using cumulative ranking curves.

Results

1024 articles were searched, and only 9 studies were screened and included in this meta-analysis with 71793 randomized participants. Sotagliflozin (HR 0.72 95%CI 0.59-0.88, SUCAR=0.93) and canagliflozin (HR 0.80 95%CI 0.67-0.97, SUCAR=0.73) can significantly reduce the risk of MACE compared with placebo. Canagliflozin (HR 0.64 95%CI 0.48-0.86, SUCAR=0.73), sotagliflozin (HR 0.66 95%CI 0.50-0.87, SUCAR=0.69) and empagliflozin (HR 0.65 95%CI 0.43-0.98, SUCAR=0.68) can significantly reduce the risk of HHF compared with placebo. Empagliflozin (HR 0.62 95%CI 0.43-0.89, SUCAR=0.96) can significantly reduce the risk of CVD compared with placebo. Empagliflozin (HR 0.61 95%CI 0.39-0.96, SUCAR=0.74), canagliflozin (HR 0.66 95%CI 0.46-0.92, SUCAR=0.63), and dapagliflozin (HR 0.53 95%CI 0.32-0.85, SUCAR=0.88) can significantly reduce the risk of RCO compared with placebo. Finerenone has reduced the risk of MACE, MI, HHF, CVD and RCO to varying degrees, but they do not show significant difference from placebo and each SGLT2i.

Conclusion

Both SGLT2i and finerenone could reduce the risk of MACE, HHF, MI, CVD, RCO. Finerenone has no obvious advantage than SGLT2i on the effects of cardiovascular and renal protective.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022375092.

Therapeutic mechanism and clinical application of Chinese herbal medicine against diabetic kidney disease

Diabetic kidney disease (DKD) is the major complications of type 1 and 2 diabetes, and is the predominant cause of chronic kidney disease and end-stage renal disease. The treatment of DKD normally consists of controlling blood glucose and improving kidney function. The blockade of renin-angiotensin-aldosterone system and the inhibition of sodium glucose cotransporter 2 (SGLT2) have become the first-line therapy of DKD, but such treatments have been difficult to effectively block continuous kidney function decline, eventually resulting in kidney failure and cardiovascular comorbidities. The complex mechanism of DKD highlights the importance of multiple therapeutic targets in treatment. Chinese herbal medicine (active compound, extract and formula) synergistically improves metabolism regulation, suppresses oxidative stress and inflammation, inhibits mitochondrial dysfunction, and regulates gut microbiota and related metabolism via modulating GLP-receptor, SGLT2, Sirt1/AMPK, AGE/RAGE, NF-κB, Nrf2, NLRP3, PGC-1α, and PINK1/Parkin pathways. Clinical trials prove the reliable evidences for Chinese herbal medicine against DKD, but more efforts are still needed to ensure the efficacy and safety of Chinese herbal medicine. Additionally, the ideal combined therapy of Chinese herbal medicine and conventional medicine normally yields more favorable benefits on DKD treatment, laying the foundation for novel strategies to treat DKD.

Drug transporters OAT1 and OAT3 have specific effects on multiple organs and gut microbiome as revealed by contextualized metabolic network reconstructions

In vitro and in vivo studies have established the organic anion transporters OAT1 (SLC22A6, NKT) and OAT3 (SLC22A8) among the main multi-specific "drug" transporters. They also transport numerous endogenous metabolites, raising the possibility of drug-metabolite interactions (DMI). To help understand the role of these drug transporters on metabolism across scales ranging from organ systems to organelles, a formal multi-scale analysis was performed. Metabolic network reconstructions of the omics-alterations resulting from Oat1 and Oat3 gene knockouts revealed links between the microbiome and human metabolism including reactions involving small organic molecules such as dihydroxyacetone, alanine, xanthine, and p-cresol-key metabolites in independent pathways. Interestingly, pairwise organ-organ interactions were also disrupted in the two Oat knockouts, with altered liver, intestine, microbiome, and skin-related metabolism. Compared to older models focused on the "one transporter-one organ" concept, these more sophisticated reconstructions, combined with integration of a multi-microbial model and more comprehensive metabolomics data for the two transporters, provide a considerably more complex picture of how renal "drug" transporters regulate metabolism across the organelle (e.g. endoplasmic reticulum, Golgi, peroxisome), cellular, organ, inter-organ, and inter-organismal scales. The results suggest that drugs interacting with OAT1 and OAT3 can have far reaching consequences on metabolism in organs (e.g. skin) beyond the kidney. Consistent with the Remote Sensing and Signaling Theory (RSST), the analysis demonstrates how transporter-dependent metabolic signals mediate organ crosstalk (e.g., gut-liver-kidney) and inter-organismal communication (e.g., gut microbiome-host).

Therapeutic role of mesenchymal stem cells (MSCs) in diabetic kidney disease (DKD)

Findings of preclinical studies and recent phase I/II clinical trials have shown that mesenchymal stem cells (MSCs) play a significant role in the development of diabetic kidney disease (DKD). Thus, MSCs have attracted increasing attention as a novel regenerative therapy for kidney diseases. This review summarizes recent literature on the roles and potential mechanisms, including hyperglycemia regulation, anti-inflammation, anti-fibrosis, pro-angiogenesis, and renal function protection, of MSC-based treatment methods for DKD. This review provides novel insights into understanding the pathogenesis of DKD and guiding the development of biological therapies.

Repurposing SGLT2 Inhibitors for Neurological Disorders: A Focus on the Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a substantially increasing incidence rate. It is characterized by repetitive behavior, learning difficulties, deficits in social communication, and interactions. Numerous medications, dietary supplements, and behavioral treatments have been recommended for the management of this condition, however, there is no cure yet. Recent studies have examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitors in neurodevelopmental diseases, based on their proved anti-inflammatory effects, such as downregulating the expression of several proteins, including the transforming growth factor beta (TGF-β), interleukin-6 (IL-6), C-reactive protein (CRP), nuclear factor κB (NF-κB), tumor necrosis factor alpha (TNF-α), and the monocyte chemoattractant protein (MCP-1). Furthermore, numerous previous studies revealed the potential of the SGLT2 inhibitors to provide antioxidant effects, due to their ability to reduce the generation of free radicals and upregulating the antioxidant systems, such as glutathione (GSH) and superoxide dismutase (SOD), while crossing the blood brain barrier (BBB). These properties have led to significant improvements in the neurologic outcomes of multiple experimental disease models, including cerebral oxidative stress in diabetes mellitus and ischemic stroke, Alzheimer's disease (AD), Parkinson's disease (PD), and epilepsy. Such diseases have mutual biomarkers with ASD, which potentially could be a link to fill the gap of the literature studying the potential of repurposing the SGLT2 inhibitors' use in ameliorating the symptoms of ASD. This review will look at the impact of the SGLT2 inhibitors on neurodevelopmental disorders on the various models, including humans, rats, and mice, with a focus on the SGLT2 inhibitor canagliflozin. Furthermore, this review will discuss how SGLT2 inhibitors regulate the ASD biomarkers, based on the clinical evidence supporting their functions as antioxidant and anti-inflammatory agents capable of crossing the blood-brain barrier (BBB).

Use of Glucose-Lowering Agents in Diabetes and CKD

Diabetes is the most common cause of kidney failure worldwide. Patients with diabetes and chronic kidney disease (CKD) are also at markedly higher risk of cardiovascular disease, particularly heart failure (HF), and death. Through the processes of gluconeogenesis and glucose reabsorption, the kidney plays a central role in glucose homeostasis. Insulin resistance is an early alteration observed in CKD, worsened by the frequent presence of hypertension, obesity, and ongoing chronic inflammation, and oxidative stress. Management of diabetes in moderate to severe CKD warrants special consideration because of changes in glucose and insulin homeostasis and altered metabolism of glucose-lowering therapies. Kidney failure and initiation of kidney replacement therapy by dialysis adds to management complexity by further limiting therapeutic options, and predisposing individuals to hypoglycemia and hyperglycemia. Glycemic goals should be individualized, considering CKD severity, presence of macrovascular and microvascular complications, and life expectancy. A general hemoglobin A1c (HbA1c) goal of approximately 7% may be appropriate in earlier stages of CKD, with more relaxed targets often appropriate in later stages. Use of sodium glucose cotransporter2 (SGLT2) inhibitors and glucagon like peptide-1 receptor agonists (GLP-1RAs) meaningfully improves kidney and heart outcomes for patients with diabetes and CKD, irrespective of HbA1c targets, and are now part of guideline-directed medical therapy in this high-risk population. Delivery of optimal care for patients with diabetes and CKD will require collaboration across health care specialties and disciplines.

Intravital imaging of hemodynamic glomerular effects of enalapril or/and empagliflozin in STZ-diabetic mice

Background: Diabetic kidney disease is the leading cause of end-stage renal disease. Administration of ACE inhibitors or/and SGLT2 inhibitors show renoprotective effects in diabetic and other kidney diseases. The underlying renoprotective mechanisms of SGLT2 inhibition, especially in combination with ACE inhibition, are incompletely understood. We used longitudinal intravital microscopy to directly elucidate glomerular hemodynamics on a single nephron level in response to the ACE inhibitor enalapril or/and the SGLT2 inhibitor empagliflozin.

Methods: Five weeks after the induction of diabetes by streptozotocin, male C57BL/6 mice were treated with enalapril, empagliflozin, enalapril/empagliflozin or placebo for 3 days. To identify hemodynamic regulation mechanisms, longitudinal intravital multiphoton microscopy was employed to measure single nephron glomerular filtration rate (snGFR) and afferent/efferent arteriole width.

Results: Diabetic mice presented a significant hyperfiltration. Compared to placebo treatment, snGFR was reduced in response to enalapril, empagliflozin, or enalapril/empagliflozin administration under diabetic conditions. While enalapril treatment caused significant dilation of the efferent arteriole (12.55 ± 1.46 µm vs. control 11.92 ± 1.04 µm, p < 0.05), empagliflozin led to a decreased afferent arteriole diameter (11.19 ± 2.55 µm vs. control 12.35 ± 1.32 µm, p < 0.05) in diabetic mice. Unexpectedly under diabetic conditions, the combined treatment with enalapril/empagliflozin had no effects on both afferent and efferent arteriole diameter change.

Conclusion: SGLT2 inhibition, besides ACE inhibition, is an essential hemodynamic regulator of glomerular filtration during diabetes mellitus. Nevertheless, additional mechanisms—independent from hemodynamic regulation—are involved in the nephroprotective effects especially of the combination therapy and should be further explored in future studies.

The effect of preoperative sodium-glucose cotransporter 2 inhibitors on the incidence of perioperative metabolic acidosis: A retrospective cohort study

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors are a novel class of anti-hyperglycemic agents. Although several cases of perioperative euglycemic diabetic ketoacidosis have been linked to these medications, the association remains unclear. This study aimed to examine the association between sodium-glucose cotransporter 2 inhibitor use and the incidence of perioperative metabolic acidosis with euglycemia, the surrogating outcome of perioperative euglycemic diabetic ketoacidosis.

METHOD

This was a retrospective, matched cohort study, which was conducted in the intensive care unit of a tertiary care facility in Japan. We identified patients aged 20 years or older with diabetes mellitus who received pharmacologic therapy and were admitted to the intensive care unit after elective surgery between April 2014 and March 2019. We extracted the following data from the electronic medical record for matching: age, sex, surgery year, surgical site, hemoglobin A1c level, and prescription for sodium-glucose cotransporter 2 inhibitors. Eligible patients were divided into two groups, those who were prescribed sodium-glucose cotransporter 2 inhibitors (SGLT2-i group) and those who were not (control group). For each patient in the SGLT2-i group, we randomly selected four patients from the control group matched for the extracted characteristics. The primary outcome was the incidence of metabolic acidosis with an elevated anion gap and euglycemia. The secondary outcome was the lowest pH value of each patient during their ICU stay.

RESULTS

A total of 155 patients were included in this study. Patients receiving sodium-glucose cotransporter 2 inhibitors had comparable characteristics to control participants; however, the proportions of patients undergoing dialysis were not similar. Metabolic acidosis with euglycemia was seen in 7/31 (22.6%) patients receiving sodium-glucose cotransporter 2 inhibitors and in 10/124 (8.1%) control patients (p = 0.047).

CONCLUSIONS

This study shows that the use of sodium-glucose cotransporter 2 inhibitors is associated with a significantly higher incidence of metabolic acidosis with euglycemia. Patients receiving sodium-glucose cotransporter 2 inhibitors who are scheduled to undergo invasive surgical procedures should be closely monitored for the development of euglycemic diabetic ketoacidosis.

Puerarin attenuates diabetic kidney injury through interaction with Guanidine nucleotide-binding protein Gi subunit alpha-1 (Gnai1) subunit

Radix puerariae, a traditional Chinese herbal medication, has been used to treat patients with diabetic kidney disease (DKD). Our previous studies demonstrated that puerarin, the active compound of radix puerariae, improves podocyte injury in type 1 DKD mice. However, the direct molecular target of puerarin and its underlying mechanisms in DKD remain unknown. In this study, we confirmed that puerarin also improved DKD in type 2 diabetic db/db mice. Through RNA-sequencing odf isolated glomeruli, we found that differentially expressed genes (DEGs) that were altered in the glomeruli of these diabetic mice but reversed by puerarin treatment were involved mostly in oxidative stress, inflammatory and fibrosis. Further analysis of these reversed DEGs revealed protein kinase A (PKA) was among the top pathways. By utilizing the drug affinity responsive target stability method combined with mass spectrometry analysis, we identified guanine nucleotide-binding protein Gi alpha-1 (Gnai1) as the direct binding partner of puerarin. Gnai1 is an inhibitor of cAMP production which is known to have protection against podocyte injury. In vitro, we showed that puerarin not only interacted with Gnai1 but also increased cAMP production in human podocytes and mouse diabetic kidney in vivo. Puerarin also enhanced CREB phosphorylation, a downstream transcription factor of cAMP/PKA. Overexpression of CREB reduced high glucose-induced podocyte apoptosis. Inhibition of PKA by Rp-cAMP also diminished the effects of puerarin on high glucose-induced podocyte apoptosis. We conclude that the renal protective effects of puerarin are likely through inhibiting Gnai1 to activate cAMP/PKA/CREB pathway in podocytes.

Changes of gut microbiota in diabetic nephropathy and its effect on the progression of kidney injury

PURPOSE

We aimed to illustrate gut microbiota and short chain fatty acid (SCFA) levels in diabetic nephropathy (DN) patients, and investigate the mechanism of sodium butyrate in diabetic mellitus (DM) rats.

METHODS

Gut microbiota and serum SCFA levels were measured by 16S rDNA and GC-MS. After being built by streptozotocin (DM rats), the DM rats were administered 300 mg/kg sodium butyrate for 12 weeks (DM + BU rats). Gut microbiota, serum and fecal butyrate level were measured. RT-PCR, WB and transmission electron microscopy were performed to explore LC3mRNA or LC3B protein expression, and autophagosomes in kidney tissues. AMPK/mTOR protein expression in renal tissue were also measured.

RESULTS

The gut microbial dysbiosis was found in DM and DN groups, and some SCFAs-producing bacteria were decreased in DN group. The serum butyrate concentrations were lower in SCFA-DN group compared with SCFA-HC group and SCFA-DM group in the other cohort. Serum butyrate level was positively correlated with eGFR. Sodium butyrate increased serum and fecal butyrate levels, and improved the enlargement of glomerular area and fibronectin and collagen IV expressions in renal tissues in DM + BU rats. The LC3 mRNA, LC3BII/I ratio and number of autophagosomes were increased in renal tissue of DM + BU rats. Higher p-AMPK/AMPK ratio and lower p-mTOR/ mTOR ratio were shown in renal tissue of DM + BU rats compared with DM rats.

CONCLUSIONS

We found the decrease in SCFAs-producing bacteria and low SCFAs concentrations in DN patients. Oral butyrate supplementation may improve kidney injury in DM rats, possibly by increasing autophagy via activating AMPK/mTOR pathway.

Efficacy and Safety of "Bushen Huoxue Therapy"-Based Combined Chinese and Western Medicine Treatment for Diabetic Kidney Disease: an Updated Meta-Analysis of 2105 Patients

BACKGROUND

Diabetic kidney disease (DKD) is the most important cause of the end-stage renal disease (ESRD) and the main cause of renal replacement therapy. Excessive inflammatory response and renal fibrosis are the keys to the development of this disease, and the conventional Western medical treatment is difficult to achieve and obtain long-term stable clinical results in all patients with DKD. Many studies have shown that Chinese medicine as a complementary and alternative medicine may be another therapeutic option to mitigate the progression of DKD to ESRD. In recent years, many doctors have used the Bushen Huoxue therapy to assist Western medicine in the treatment of the disease and have achieved certain clinical effects. However, most of the current studies are small sample studies, and there is no evidence-based confirmation.

OBJECTIVE

To systematically evaluate the efficacy and safety of the Bushen Huoxue therapy combined with conventional Western medicine in the treatment of DKD.

METHODS

A comprehensive search of literature databases such as CNKI, Wanfang, Pubmed, and Cochrane Library was conducted. The screening condition was that the control group was treated with conventional Western medicine and the experimental group was treated with Bushen Huoxue therapy's RCT on top of the control group, and the RCTs were published from January 2011 to October 2021. The Cochrane risk bias assessment tool was used for literature quality evaluation, and RevMan 5.3 software was used for statistical analysis.

RESULTS

A total of 23 RCTs were finally included, with a total of 2,105 patients. Meta-analysis results show that the experimental group can effectively improve the clinical efficacy (RR = 1.28, 95% CI (1.22, 1.34), P < 0.01), significantly reduce Crea (SMD = -0.45, 95% CI (-0.57, -0.33), P < 0.01), 24 h UTP (SMD = -0.57, 95% CI (-0.69, -0.45), P < 0.01), BUN (SMD = -0.36, 95%CI (-0.48, -0.24), P < 0.01), UAER (SMD = -1.58, 95% CI (-1.78, -1.37), P < 0.01), and blood sugar, and have certain medication safety (RR = 0.00, 95% CI (-0.03, 0.03), P=0.87).

CONCLUSIONS

Chinese medicine based on the Bushen Huoxue therapy has a good clinical effect in the treatment of diabetic kidney disease and has certain safety. However, due to the limitation of the quality and quantity of the included literature, the above conclusion still needs more rational experiments to further verify.

Kidney Damage Caused by Obesity and Its Feasible Treatment Drugs

The rapid growth of obesity worldwide has made it a major health problem, while the dramatic increase in the prevalence of obesity has had a significant impact on the magnitude of chronic kidney disease (CKD), especially in developing countries. A vast amount of researchers have reported a strong relationship between obesity and chronic kidney disease, and obesity can serve as an independent risk factor for kidney disease. The histological changes of kidneys in obesity-induced renal injury include glomerular or tubular hypertrophy, focal segmental glomerulosclerosis or bulbous sclerosis. Furthermore, inflammation, renal hemodynamic changes, insulin resistance and lipid metabolism disorders are all involved in the development and progression of obesity-induced nephropathy. However, there is no targeted treatment for obesity-related kidney disease. In this review, RAS inhibitors, SGLT2 inhibitors and melatonin would be presented to treat obesity-induced kidney injury. Furthermore, we concluded that melatonin can protect the kidney damage caused by obesity by inhibiting inflammation and oxidative stress, revealing its therapeutic potential.

The cell membrane repair protein MG53 modulates transcription factor NF-κB signaling to control kidney fibrosis

Kidney fibrosis is associated with the progression of acute kidney injury to chronic kidney disease. MG53, a cell membrane repair protein, has been shown to protect against injury to kidney epithelial cells and acute kidney injury. Here, we evaluated the role of MG53 in modulation of kidney fibrosis in aging mice and in mice with unilateral ureteral obstruction (UUO) a known model of progressive kidney fibrosis. Mice with ablation of MG53 developed more interstitial fibrosis with age than MG53-intact mice of the same age. Similarly, in the absence of MG53, kidney fibrosis was exaggerated compared to mice with intact MG53 in the obstructed kidney compared to the contralateral unobstructed kidney or the kidneys of sham operated mice. The ureteral obstructed kidneys from MG53 deficient mice also showed significantly more inflammation than ureteral obstructed kidneys from MG53 intact mice. In vitro experiments demonstrated that MG53 could enter the nuclei of proximal tubular epithelial cells and directly interact with the p65 component of transcription factor NF-κB, providing a possible explanation of enhanced inflammation in the absence of MG53. To test this, enhanced MG53 expression through engineered cells or direct recombinant protein delivery was given to mice subject to UUO. This reduced NF-κB activation and inflammation and attenuated kidney fibrosis. Thus, MG53 may have a therapeutic role in treating chronic kidney inflammation and thereby provide protection against fibrosis that leads to the chronic kidney disease phenotype.

Glucose Metabolism in Acute Kidney Injury and Kidney Repair

The kidneys play an indispensable role in glucose homeostasis via glucose reabsorption, production, and utilization. Conversely, aberrant glucose metabolism is involved in the onset, progression, and prognosis of kidney diseases, including acute kidney injury (AKI). In this review, we describe the regulation of glucose homeostasis and related molecular factors in kidneys under normal physiological conditions. Furthermore, we summarize recent investigations about the relationship between glucose metabolism and different types of AKI. We also analyze the involvement of glucose metabolism in kidney repair after injury, including renal fibrosis. Further research on glucose metabolism in kidney injury and repair may lead to the identification of novel therapeutic targets for the prevention and treatment of kidney diseases.

Regression of diabetic nephropathy by treatment with empagliflozin in BTBR ob/ob mice

BACKGROUND

The SGLT2 inhibitor empagliflozin lowers blood glucose via reduced tubular reabsorption of filtered glucose and is an important new therapy for diabetic nephropathy (DN). This study tested whether treatment with empagliflozin would ameliorate proteinuria and the pathologic alterations of DN including podocyte number and integrity in the leptin deficient BTBR ob/ob mouse model of DN.

METHODS

Study cohorts included wild type BTBR mice, untreated diabetic BTBR ob/ob mice, and mice treated with empagliflozin for six weeks after development of established DN at 18 weeks of age.

RESULTS

Hyperglycemia, proteinuria, serum creatinine, accumulation of mesangial matrix and the extent of mesangiolysis were reversed with empagliflozin treatment. Treatment with empagliflozin resulted in increased podocyte number and podocyte density, improvement in the degree of podocyte foot process effacement and parietal epithelial cell activation. SGLT2 inhibition reduced renal oxidative stress, measured by urinary excretion of markers of RNA/DNA damage and in situ demonstration of decreased carbonyl oxidation. There was no discernable difference in accumulations of advanced glycation endproducts by immunohistochemistry.

CONCLUSION

The structural improvements seen in BTBR ob/ob mice treated with empagliflozin provide insight into potential long term benefits for humans with DN, for whom there is no comparable biopsy information to identify structural changes effected by SGLT2 inhibition. The findings suggest SGLT2 inhibition may ameliorate diabetic nephropathy through glucose lowering-dependent and -independent mechanisms that lead to podocyte restoration and delay or reversal of the disease progress.

Lipid Disorders in NAFLD and Chronic Kidney Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver dysfunction and is characterized by exaggerated lipid accumulation, inflammation and even fibrosis. It has been shown that NAFLD increases the risk of other chronic diseases, particularly chronic kidney disease (CKD). Lipid in excess could lead to liver and kidney lesions and even end-stage disease through diverse pathways. Dysregulation of lipid uptake, oxidation or de novo lipogenesis contributes to the toxic effects of ectopic lipids which promotes the development and progression of NAFLD and CKD via triggering oxidative stress, apoptosis, pro-inflammatory and profibrotic responses. Importantly, dyslipidemia and release of pro-inflammatory cytokines caused by NAFLD (specifically, nonalcoholic steatohepatitis) are considered to play important roles in the pathological progression of CKD. Growing evidence of similarities between the pathogenic mechanisms of NAFLD and those of CKD has attracted attention and urged researchers to discover their common therapeutic targets. Here, we summarize the current understanding of molecular aberrations underlying the lipid metabolism of NAFLD and CKD and clinical evidence that suggests the relevance of these pathways in humans. This review also highlights the orchestrated inter-organ cross-talk in lipid disorders, as well as therapeutic options and opportunities to counteract NAFLD and CKD.

Pharmacokinetic/Pharmacodynamic Properties and Clinical Use of SGLT2 Inhibitors in Non-Asian and Asian Patients with Type 2 Diabetes and Chronic Kidney Disease

Chronic kidney disease is a prevalent complication of type 2 diabetes mellitus (T2DM). Sodium-glucose cotransporter type 2 inhibitors (SGLT2is) have a unique mode of action targeting the kidney. As their glucose-lowering potency declines with the reduction in estimated glomerular filtration rate, their clinical use in patients with T2DM with chronic kidney disease has been submitted to restriction. However, recent observations demonstrated that SGLT2is reduce the progression of renal impairment in patients with mild-to-moderate chronic kidney disease, with or without albuminuria. Furthermore, SGLT2is reduce the incidence of cardiovascular events in patients with T2DM at high cardiovascular risk, independently of baseline estimated glomerular filtration rate. Thus, recent guidelines recommend the prescription of SGLT2is in patients with T2DM with mild-to-moderate chronic kidney disease defined by an estimated glomerular filtration rate between ≥ 30 and < 90 mL/min/1.73 m² and/or albuminuria. The present comprehensive review describes the pharmacokinetic/pharmacodynamic properties of SGLT2is commercialised worldwide and in Japan in patients with T2DM with mild, moderate and severe chronic kidney disease. Drug exposure increases when the estimated glomerular filtration rate declines but without a clear-cut relationship with the severity of chronic kidney disease and in a rather moderate amplitude that most often does not require a dose reduction in the presence of mild-to-moderate chronic kidney disease. The urinary glucose excretion steadily declines with the reduction in estimated glomerular filtration rate. This may explain a lower effect on glucose control, yet the positive effects on body weight and blood pressure still remain. The efficacy and safety of these SGLT2is are analysed among patients with stages 3a and 3b chronic kidney disease in placebo-controlled randomised clinical trials, with almost similar results in Asian and non-Asian individuals with T2DM. In summary, there is no reason not to prescribe SGLT2is in patients with T2DM with mild-to-moderate chronic kidney disease, especially if the aim is to benefit from cardiovascular and/or renal protection.

Clinical efficacies, underlying mechanisms and molecular targets of Chinese medicines for diabetic nephropathy treatment and management

Diabetic nephropathy (DN) has been recognized as a severe complication of diabetes mellitus and a dominant pathogeny of end-stage kidney disease, which causes serious health problems and great financial burden to human society worldwide. Conventional strategies, such as renin-angiotensin-aldosterone system blockade, blood glucose level control, and bodyweight reduction, may not achieve satisfactory outcomes in many clinical practices for DN management. Notably, due to the multi-target function, Chinese medicine possesses promising clinical benefits as primary or alternative therapies for DN treatment. Increasing studies have emphasized identifying bioactive compounds and molecular mechanisms of reno-protective effects of Chinese medicines. Signaling pathways involved in glucose/lipid metabolism regulation, antioxidation, anti-inflammation, anti-fibrosis, and podocyte protection have been identified as crucial mechanisms of action. Herein, we summarize the clinical efficacies of Chinese medicines and their bioactive components in treating and managing DN after reviewing the results demonstrated in clinical trials, systematic reviews, and meta-analyses, with a thorough discussion on the relative underlying mechanisms and molecular targets reported in animal and cellular experiments. We aim to provide comprehensive insights into the protective effects of Chinese medicines against DN.

Effects of Food on the Pharmacokinetic Properties and Mass Balance of Henagliflozin in Healthy Male Volunteers

PURPOSE

Henagliflozin is a highly selective and effective sodium glucose co-transporter (SGLT)-2 inhibitor developed for the treatment of patients with type 2 diabetes mellitus (T2DM). This study aimed to investigate the effects of meal intake on the pharmacokinetic properties of henagliflozin, and to understand the excretion pathways of henagliflozin in humans.

METHODS

In this Phase I, randomized, open-label, single-dose, two-period crossover study, 12 healthy male Chinese volunteers were randomized to receive either henagliflozin 10 mg in the fasted condition followed by henagliflozin 10 mg in the fed condition, or the reverse schedule, with the two administrations separated by a washout period of at least 7 days. Samples of blood, urine, and feces were collected and analyzed for the investigation of the pharmacokinetic profile and excretion pathways in the fasted and fed conditions. Any adverse events that occurred throughout the study were recorded for tolerability assessment.

FINDINGS

After the administration of a single oral dose of henagliflozin, mean (SD) plasma AUC_0-∞ and C_max were 1200 (274) h · ng/mL and 179 (48.8) ng/mL, respectively, in the fasted state and were decreased to 971 (245) h · ng/mL and 115 (34.2) ng/mL in the fed state. The fed/fasted ratios (90% CIs) of the geometric mean values of C_max, AUC_0-t, and AUC_0-∞ were 64% (54%-76%), 80% (76%-85%), and 80% (76%-85%), respectively. The median (range) T_max was prolonged from 1.5 (1-3) hours in the fasted condition to 2 (1.5-6) hours in the fed condition. Mass-balance testing revealed that henagliflozin was eliminated primarily as the parent drug in feces and as glucuronide metabolites in urine. In the fasted state, the cumulative excretion percentages of the parent drug and its metabolites to dose in feces and urine were 40.6% and 33.9%, respectively. The values in the fed condition were changed to 50.4% and 25.5%, respectively. These findings suggest that postprandial administration decreases the absorption rate and the extent of henagliflozin exposure in humans, but has no effect on the metabolism or elimination of the drug.

IMPLICATIONS

In the present study, the consumption of a high-fat meal prior to henagliflozin administration was associated with reductions in AUC_0-∞ and C_max of 19.4% and 36.4%, respectively. However, based on the analysis of the pharmacokinetic/pharmacodynamic findings on henagliflozin, this slight change may not have clinical significance. Mass balance of henagliflozin in humans was achieved with ∼75% of the administered dose recovered in excretions within 4 days after administration whether in the fasted or fed state. These findings suggest that henagliflozin tablets can be administered with or without food.

Network Pharmacology Combined with Bioinformatics to Investigate the Mechanisms and Molecular Targets of Astragalus Radix-Panax notoginseng Herb Pair on Treating Diabetic Nephropathy

Background

Astragalus Radix (AR)-Panax notoginseng (PN), a classical herb pair, has shown significant effects in treating diabetic nephropathy (DN). However, the intrinsic mechanism of AR-PN treating DN is still unclear. This study aims to illustrate the mechanism and molecular targets of AR-PN treating DN based on network pharmacology combined with bioinformatics.

Materials and Methods

The Traditional Chinese Medicine Systems Pharmacology database was used to screen bioactive ingredients of AR-PN. Subsequently, putative targets of bioactive ingredients were predicted utilizing the DrugBank database and converted into genes on UniProtKB database. DN-related targets were retrieved via analyzing published microarray data (GSE30528) from the Gene Expression Omnibus database. Protein-protein interaction networks of AR-PN putative targets and DN-related targets were established to identify candidate targets using Cytoscape 3.8.0. GO and KEGG enrichment analyses of candidate targets were reflected using a plugin ClueGO of Cytoscape. Molecular docking was performed using AutoDock Vina software, and the results were visualized by Pymol software. The diagnostic capacity of hub genes was verified by receiver operating characteristic (ROC) curves.

Results

Twenty-two bioactive ingredients and 189 putative targets of AR-PN were obtained. Eight hundred and fifty differently expressed genes related to DN were screened. The PPI network showed that 115 candidate targets of AR-PN against DN were identified. GO and KEGG analyses revealed that candidate targets of AR-PN against DN were mainly involved in the apoptosis, oxidative stress, cell cycle, and inflammation response, regulating the PI3K-Akt signaling pathway, cell cycle, and MAPK signaling pathway. Moreover, MAPK1, AKT1, GSK3B, CDKN1A, TP53, RELA, MYC, GRB2, JUN, and EGFR were considered as the core potential therapeutic targets. Molecular docking demonstrated that these core targets had a great binding affinity with quercetin, kaempferol, isorhamnetin, and formononetin components. ROC curve analysis showed that AKT1, TP53, RELA, JUN, CDKN1A, and EGFR are effective in discriminating DN from controls.

Conclusions

AR-PN against DN may exert its renoprotective effects via various bioactive chemicals and the related pharmacological pathways, involving multiple molecular targets, which may be a promising herb pair treating DN. Nevertheless, these results should be further validated by experimental evidence.