Risks of Metformin in Type 2 Diabetes and Chronic Kidney Disease: Lessons Learned from Taiwanese Data

The role of basal insulins in the treatment of people with type 2 diabetes and chronic kidney disease: A narrative review

The majority of cases of chronic kidney disease (CKD) worldwide are driven by the presence of type 2 diabetes (T2D), resulting in an increase in CKD rates over the past few decades. The existence of CKD alongside diabetes is associated with increased burden of cardiovascular disease and increased risk of death. Optimal glycaemic control is essential to prevent progression of CKD, but achieving glycaemic targets in people with CKD and diabetes can be challenging because of increased risk of hypoglycaemia and limitations on glucose-lowering therapeutic options. This review considers the challenges in management of T2D in people with impaired kidney function and assesses evidence for use of basal insulin analogues in people with CKD.

Structural characterization of a polysaccharide from Abelmoschus esculentus L. Moench (okra) and its hypoglycemic effect and mechanism on type 2 diabetes mellitus

A novel acidic polysaccharide named AeP-P-1 was prepared from Abelmoschus esculentus L. Moench (okra).

Novel management of diabetes in kidney transplantation

PURPOSE OF REVIEW

Posttransplant diabetes mellitus (PTDM) is a prevalent complication in kidney transplant recipients, and has been associated with worse short-term and long-term outcomes.

RECENT FINDINGS

While hyperglycemia is frequently seen in the early posttransplant period because of surgical stress, infection, and use of high-dose steroids, the diagnosis of PTDM should be established after patients are clinically stable and on stable maintenance immunosuppression. In the early posttransplant period, hyperglycemia is typically treated with insulin, and pilot data have suggested potential benefit of lower vs. higher glycemic targets in this setting. Growing data indicate lifestyle modifications, including dietary interventions, physical activity, and mitigation of obesity, are associated with improved posttransplant outcomes. While there are limited data to support a first-line antidiabetic medication for PTDM, more established pharmacotherapies such as sulfonylureas, meglitinides, and dipetidyl peptidase IV inhibitors are commonly used. Given recent trials showing the benefits of sodium-glucose cotransporter 2 inhibitors and glucagon-like peptide 1 receptor agonists upon kidney outcomes in nontransplant patients, further study of these agents specifically in kidney transplant recipients are urgently needed.

SUMMARY

Increasing evidence supports a multidisciplinary approach, including lifestyle modification, obesity treatment, judicious immunosuppression selection, and careful utilization of novel antidiabetic therapies in PTDM patients.

Metformin and the Risk of Anemia of Advanced Chronic Kidney Disease in Patients With Type 2 Diabetes Mellitus

This retrospective cohort study determines whether metformin monotherapy or combination therapies can decrease anemia risk in the progress of advanced chronic kidney disease for patients with type 2 diabetes mellitus. The data set was obtained from the National Health Insurance Research Database, containing 1 million randomly selected beneficiaries. After matching, 9303 pairs (1:1) of metformin users and nonusers were acquired. Every patient was individually recorded from 1997 to 2012 to identify anemia incidence (hemoglobin <9 gm/dL). Cox regression models were used to compute hazard ratios and 95% confidence intervals (CIs). There were 305 (0.7%) and 76 (0.8%) erythropoietin-stimulating agent cases in the metformin and non-metformin cohorts over a mean follow-up period of 6.8 and 5.6 years. After matching, the use of metformin decreased the risk of usage of erythropoietin-stimulating agents with an adjusted hazard ratio of 0.76 (95%CI, 0.45-1.29) for dosage of <357 g to 0.30 (95%CI, 0.17-0.56) for >1368 g. The combination of metformin and dipeptidyl peptidase-4 inhibitors decreased with a hazard ratio of 0.42 (95%CI, 0.18-0.99), compared to metformin alone. Metformin combined with dipeptidyl peptidase-4 inhibitors is superior to metformin monotherapy or non-metformin antidiabetic therapies for reducing the risk of anemia in the progress of advanced chronic kidney disease among patients with type 2 diabetes.

Vitamin D3 potentiates the nephroprotective effects of metformin in a rat model of metabolic syndrome: role of AMPK/SIRT1 activation and DPP-4 inhibition

The current study aimed to investigate the molecular mechanisms of metformin and vitamin D3-induced nephroprotection in a metabolic syndrome (MetS) rat model, evaluating the capacity of vitamin D3 to potentiate metformin action. MetS was induced by 10% fructose in drinking water and 3% salt in the diet. After 6 weeks, serum lipid profile and uric acid were measured, an oral glucose tolerance test (OGTT) was performed, and kidney function was investigated. In conjunction with the same concentrations of fructose and salt feeding, MetS rats with significant weight gain, dyslipidemia, hyperuricemia, and dysglycemia were treated orally with metformin (200 mg/kg), vitamin D3 (10 µg/kg), or both daily for 6 weeks. At the end of the study period, anthropometrical parameters were recorded, OGTT was reperformed, urine and blood samples were collected, and tissue samples were harvested at sacrifice. MetS rats showed dramatically declined renal function, enhanced intrarenal oxidative stress and inflammation, and extravagant renal histopathological damage with interstitial fibrosis. Metformin and vitamin D3 significantly reversed all the aforementioned deleterious effects in MetS rats. The study has verified the nephroprotective effects of metformin and vitamin D3 in MetS, accentuating the critical role of AMP-activated protein kinase/sirtuin-1 activation and dipeptidyl peptidase-4 inhibition. Given the synergistic effects of the combination, vitamin D3 is worth being investigated as an additional therapeutic agent for preventing MetS-induced nephropathy.

Profound Metabolic Acidosis due to Metformin Intoxication Requiring Dialysis

Metformin-associated lactic acidosis (MALA) is a rare but life-threatening condition with often high mortality rates. Despite this, metformin continues to be one of the most commonly prescribed antihyperglycemic agents in the market. We present a unique case of a 61-year-old female with severe acidosis of pH = 6.72 and lactic acid of 26 mmol/L who presented obtunded after ingestion of an unknown amount of metformin. She was subsequently intubated, became hypotensive, and was initiated on vasopressors. She was swiftly started on a combination of intermittent hemodialysis (IHD) and bicarbonate therapy 7 hours after admission followed by continuous renal replacement therapy (CRRT) as she became more hemodynamically unstable. The patient's renal function improved, and she was discharged 7 days after admission with favorable sequelae. Dialysis is often reported in cases of severe MALA; however, it remains unclear how quickly dialysis should be initiated. This case aims to explore the benefits of quick initiation of extracorporeal measures in the forms of IHD and CRRT with concurrent bicarbonate supplementation. Furthermore, this case demonstrates the importance of clinical suspicion in metabolic acidosis in a patient on metformin therapy.

Is Metformin a Possible Beneficial Treatment for Psoriasis? A Scoping Review

Psoriasis is a chronic inflammatory condition with genetic, immunological, and metabolic etiology. The link between psoriasis and diabetes mellitus has been shown in genetic predisposition, environmental influences, inflammatory pathways, and insulin resistance, resulting in end-organ damage in both conditions. Because comorbidities often accompany psoriasis, the therapeutic management of the disease must also take into consideration the comorbidities. Given that metformin’s therapeutic role in psoriasis is not yet fully elucidated, we raised the question of whether metformin is a viable alternative for the treatment of psoriasis. We conducted this scoping review by searching for evidence in PubMed, Cochrane, and Scopus databases, and we used an extension for scoping reviews (PRISMA-ScR). Current evidence suggests that metformin is safe to use in psoriasis. Studies have shown an excellent therapeutic response to metformin in patients with psoriasis and comorbidities such as diabetes, metabolic syndrome, and obesity. There is no clear evidence supporting metformin monotherapy in patients with psoriasis without comorbidities. There is a need to further evaluate metformin in larger clinical trials, as a therapy in psoriasis.

Metformin: A Novel Weapon Against Inflammation

It has become widely accepted that inflammation is a driving force behind a variety of chronic diseases, such as cardiovascular disease, diabetes, kidney disease, cancer, neurodegenerative disorders, etc. However, the existing nonsteroidal anti-inflammatory drugs show a limited utility in clinical patients. Therefore, the novel agents with different inflammation-inhibitory mechanisms are worth pursuing. Metformin, a synthetic derivative of guanidine, has a history of more than 50 years of clinical experience in treating patients with type 2 diabetes. Intense research efforts have been dedicated to proving metformin’s inflammation-inhibitory effects in cells, animal models, patient records, and randomized clinical trials. The emerging evidence also indicates its therapeutic potential in clinical domains other than type 2 diabetes. Herein, this article appraises current pre-clinical and clinical findings, emphasizing metformin’s anti-inflammatory properties under individual pathophysiological scenarios. In summary, the anti-inflammatory effects of metformin are evident in pre-clinical models. By comparison, there are still clinical perplexities to be addressed in repurposing metformin to inflammation-driven chronic diseases. Future randomized controlled trials, incorporating better stratification/targeting, would establish metformin’s utility in this clinical setting.

Structure and hypoglycemic activity of a novel exopolysaccharide of Cordyceps militaris

A novel neutral exopolysaccharide (EPS-III) was isolated from culture broth of Cordyceps militaris (C. militaris). The EPS-III was a homogeneous polysaccharide with M_w of 1.56 × 10³ kDa. The yield of EPS-III from culture broth was 123.2 ± 3.1 mg/L and the sugar content was 93.32 ± 0.87%. The backbone of EPS-III was mainly consisted of →4)-α-D-Galp-(1→, while →3, 6)-α-D-Manp-(1→, →4)-α-D-Manp-(1→, →3)-β-D-Galp-(1→ and →3)-α-D-Glcp-(1→ were distributed in the backbone or in the branch chains. The EPS-III had helix structure when dissolved in weak alkaline solution. It also had branched and intertwined form on the surface. The inhibition of α-glucosidase significantly increased as the increase of purity of exopolysaccharides. The EPS-III had effective inhibition on the α-glucosidase with dose-effect relationship. Besides, the results of hypoglycemic activity analysis in vivo indicated that EPS-III can alleviate weight loss, reduce plasma glucose concentration, improve glucose tolerance, protect immune organs and repair dyslipidemia to relieve diabetes in STZ-induced diabetic mice. The manuscript first studied the hypoglycemic activity of exopolysaccharide of by C. militaris, proving and promoting the application value of culture broth. The structure characterization of EPS-III laid experimental foundations on the exploration of structure-activity relationship.

The Effects of Metformin on Age-Related Changes in the Liver Sinusoidal Endothelial Cell

Age-related changes in the liver sinusoidal endothelium, particularly the reduction in fenestrations, contribute to insulin resistance in old age. Metformin impacts on the aging process and improves insulin resistance. Therefore, the effects of metformin on the liver sinusoidal endothelium were studied. Metformin increased fenestrations in liver sinusoidal endothelial cells isolated from both young and old mice. Mice administered metformin in the diet for 12 months had increased fenestrations and this was associated with lower insulin levels. The effect of metformin on fenestrations was blocked by inhibitors of AMP-activated protein kinase (AMPK), endothelial nitric oxide synthase, and myosin light chain kinase phosphorylation. Metformin led to increased transgelin expression and structural changes in the actin cytoskeleton but had no effect on lactate production. Metformin also generated fenestration-like structures in SK-Hep1 cells, a liver endothelial cell line, and this was associated with increased ATP, cGMP, and mitochondrial activity. In conclusion, metformin ameliorates age-related changes in the liver sinusoidal endothelial cell via AMPK and endothelial nitric oxide pathways, which might promote insulin sensitivity in the liver, particularly in old age.

The effect of energy restriction on development and progression of chronic kidney disease: review of the current evidence

Energy restriction (ER) has anti-ageing effects and probably protects from a range of chronic diseases including cancer, diabetes and chronic kidney disease (CKD). Specifically, ER has a positive impact on experimental kidney ageing, CKD (diabetic nephropathy, polycystic kidney disease) and acute kidney injury (nephrotoxic, ischaemia-reperfusion injury) through such mechanisms as increased autophagy, mitochondrial biogenesis and DNA repair, and decreased inflammation and oxidative stress. Key molecules contributing to ER-mediated kidney protection include adenosine monophosphate-activated protein kinase, sirtuin-1 and PPAR-γ coactivator 1α. However, CKD is a complex condition, and ER may potentially worsen CKD complications such as protein-energy wasting, bone-mineral disorders and impaired wound healing. ER mimetics are drugs, such as metformin and Na-glucose co-transporter-2 which mimic the action of ER. This review aims to provide comprehensive data regarding the effect of ER on CKD progression and outcomes.

Hypoglycemic effects of phenolic compound-rich aqueous extract from water dropwort (Oenanthe javanica DC.) on streptozotocin-induced diabetic mice

Phenolic compounds in water dropwort aqueous extract were identified, and the IRS-2/PI3K-AKT pathway and GLUT4 translocation were regulated for hypoglycemic action.

Safety of Metformin in Psoriasis Patients With Diabetes Mellitus: A 17-Year Population-Based Real-World Cohort Study

CONTEXT

The safety of metformin usage by diabetic psoriasis patients is unclear.

OBJECTIVE

To investigate the real-world safety of metformin in psoriatic patients with type 2 diabetes mellitus (T2DM).

DESIGN

We used the National Health Insurance Research Database to perform a cohort study. Based on metformin and other antidiabetic agent prescriptions, we divided all psoriasis patients with T2DM into the metformin group and the nonmetformin group. The outcomes included all-cause mortality, severe psoriasis, hospitalization due to psoriasis, and any cause for readmission.

RESULTS

The metformin group (n = 5520) and the nonmetformin group (n = 3062) did not significantly differ in the risk of all-cause mortality [hazard ratio (HR) 1.08; 95% CI, 0.90 to 1.30], severe psoriasis (HR, 0.95; 95% CI, 0.80 to 1.09), psoriasis-related admission (HR, 1.32; 95% CI, 0.90 to 1.93), and any-cause readmission (HR, 0.99; 95% CI, 0.90 to 1.11). The dose-response analysis found no significant increase in the risk of severe psoriasis and psoriasis-related admission, even with more than 80 defined daily doses or 1000 mg daily dose of metformin prescribed (P for linear trend > 0.05).

CONCLUSION

Metformin can be prescribed for diabetic psoriasis patients without safety concerns.

Safety and efficacy of antihyperglycaemic agents in diabetic kidney disease

Diabetic kidney disease (DKD) is the major contributor to the mortality and the financial burden of diabetes, accounting for approximately 50% of the cases of end-stage renal disease (ESRD) in the developed world. Several studies have already demonstrated that achieving blood pressure targets in DKD with agents blocking the renin-angiotensin system confer superior renoprotection when compared to other agents. However, the effects on renal outcomes of antihyperglycaemic agents in these patients have not been reported or studied broadly until recent years. The intent of this article is to review the available data on safety, efficacy, impact on renal outcomes and pathophysiology implications of the most utilized antihyperglycaemic agents in DKD/ESRD.

A Challenging Case of Coexisting Type A and Type B Lactic Acidosis: A Case Report

The etiology of lactic acidosis can potentially be misleading, especially in a critically ill patient with malignancy. Type B lactic acidosis represents a rare and often lethal complication of malignancy. When differentiating the types of lactic acidosis, Type A is due to marked tissue hypoperfusion and Type B is due to causes in the setting of a normal perfused state.

We report the case of a 56-year-old male with newly diagnosed poorly differentiated neuroendocrine metastatic carcinoma and renal cell carcinoma who presented with a decreased level of consciousness and appetite. The patient was started on a sepsis protocol from an initial intensive care unit (ICU) admission. Broad spectrum antibiotics were initiated, and despite management, his mentation and respiratory status worsened, leading to intubation and mechanical ventilation. The patient continued to have elevated lactic acid and white count levels throughout the hospital course. After extensive workup and an ICU stay of 16 days, a decision was made to pursue comfort care measures and the patient passed away shortly thereafter.

The patient's persistently elevated lactic acidosis may have resulted from the inherent malignancy. The literature mentions glycolysis with enhanced metabolism as a proposed mechanism. One theory states that these changes enable cancer cells to acquire and metabolize nutrients in a way that favors proliferation over efficient adenosine triphosphate (ATP) production, resulting in elevations of lactate production. Patients presenting to the ICU with elevated lactic acid levels need to be thoroughly worked up for all potential causes. In our case, the underlying malignancies likely caused the persistently elevated lactic acidosis, despite subtherapeutic treatment and resuscitative measures.

Hypoglycemia-Related Hospitalizations and Mortality Among Patients With Diabetes Transitioning to Dialysis

RATIONALE & OBJECTIVE

Diabetic patients with declining kidney function are at heightened risk for hypoglycemia. We sought to determine whether hypoglycemia-related hospitalizations in the interval before dialysis therapy initiation are associated with post-end-stage renal disease (ESRD) mortality among incident patients with ESRD with diabetes.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

US veterans from the national Veterans Affairs database with diabetes and chronic kidney disease transitioning to dialysis therapy from October 2007 to September 2011.

EXPOSURE

Hypoglycemia-related hospitalizations during the pre-ESRD period and antidiabetic medication regimens.

OUTCOME

The outcome of post-ESRD all-cause mortality was evaluated relative to pre-ESRD hypoglycemia. The outcome of pre-ESRD hypoglycemia-related hospitalization was evaluated relative to antidiabetic medication regimens.

ANALYTIC APPROACH

We examined whether the occurrence and frequency of pre-ESRD hypoglycemia-related hospitalizations are associated with post-ESRD mortality using Cox regression models adjusted for case-mix covariates. In a subcohort of patients prescribed 0 to 2 oral antidiabetic drugs and/or insulin, we examined the 12 most commonly prescribed antidiabetic medication regimens and risk for pre-ESRD hypoglycemia-related hospitalization using logistic regression models adjusted for case-mix covariates.

RESULTS

Among 30,156 patients who met eligibility criteria, the occurrence of pre-ESRD hypoglycemia-related hospitalization(s) was associated with higher post-ESRD mortality risk: adjusted HR (aHR), 1.25; 95% CI, 1.17-1.34 (reference group: no hypoglycemia hospitalization). Increasing frequency of hypoglycemia-related hospitalizations was independently associated with incrementally higher mortality risk: aHRs of 1.21 (95% CI, 1.12-1.30), 1.47 (95% CI, 1.19-1.82), and 2.07 (95% CI, 1.46-2.95) for 1, 2, and 3 or more hypoglycemia-related hospitalizations, respectively (reference group: no hypoglycemia hospitalization). Compared with patients who were prescribed neither oral antidiabetic drugs nor insulin, medication regimens that included sulfonylureas and/or insulin were associated with higher risk for hypoglycemia.

LIMITATIONS

Residual confounding cannot be excluded.

CONCLUSIONS

Among incident patients with ESRD with diabetes, a dose-dependent relationship between frequency of pre-ESRD hypoglycemia-related hospitalizations and post-ESRD mortality was observed. Further study of diabetic management strategies that prevent hypoglycemia as patients with chronic kidney disease transition to ESRD are warranted.