Dominant PDX1 deficiency causes highly penetrant diabetes at different ages, associated with obesity and exocrine pancreatic deficiency: Lessons for precision medicine

OBJECTIVE

Heterozygous pathogenic or likely pathogenic (P/LP) PDX1 variants cause monogenic diabetes. We comprehensively examined the phenotypes of carriers of P/LP PDX1 variants, and delineated potential treatments that could be efficient in an objective of precision medicine.

METHODS

The study primarily involved a family harboring a novel P/LP PDX1 variant. We then conducted an analysis of documented carriers of P/LP PDX1 variants, from the Human Gene Mutation Database (HGMD), RaDiO study, and Type 2 Diabetes Knowledge Portal (T2DKP) including 87 K participants.

RESULTS

Within the family, we identified a P/LP PDX1 variant encoding p.G232S in four relatives. All of them exhibited diabetes, albeit with very different ages of onset (10-40 years), along with caudal pancreatic agenesis and childhood-onset obesity. In the HGMD, 79 % of carriers of a P/LP PDX1 variant displayed diabetes (with differing ages of onset from eight days of life to 67 years), 63 % exhibited pancreatic insufficiency and surprisingly 40 % had obesity. The impact of P/LP PDX1 variants on increased risk of type 2 diabetes mellitus was confirmed in the T2DKP. Dipeptidyl peptidase 4 inhibitor (DPP4i) and glucagon-like peptide-1 receptor agonist (GLP1-RA), enabled good glucose control without hypoglycemia and weight management.

CONCLUSIONS

This study reveals diverse clinical presentations among the carriers of a P/LP PDX1 variant, highlighting strong variations in diabetes onset, and unexpectedly high prevalence of obesity and pancreatic development abnormalities. Clinical data suggest that DPP4i and GLP1-RA may be the best effective treatments to manage both glucose and weight controls, opening new avenue in precision diabetic medicine.

Sweet and simple as syrup: A review and guidance for use of novel antihyperglycemic agents for post-transplant diabetes mellitus and type 2 diabetes mellitus after kidney transplantation

Uncontrolled type 2 diabetes mellitus (T2DM) and post-transplant diabetes mellitus (PTDM) increase morbidity and mortality after kidney transplantation. Conventional strategies for diabetes management in this population include metformin, sulfonylureas, meglitinides and insulin. Limitations with these agents, as well as promising new antihyperglycemic agents, create a need and opportunity to explore additional options for transplant diabetes pharmacotherapy. Novel agents including sodium glucose co-transporter 2 inhibitors (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP1RA), and dipeptidyl peptidase IV inhibitors (DPP4i) demonstrate great promise for T2DM management in the non-transplant population. Moreover, many of these agents possess renoprotective, cardiovascular, and/or weight loss benefits in addition to improved glucose control while having reduced risk of hypoglycemia compared with certain other conventional agents. This comprehensive review examines available literature evaluating the use of novel antihyperglycemic agents in kidney transplant recipients (KTR) with T2DM or PTDM. Formal grading of recommendations assessment, development, and evaluation (GRADE) system recommendations are provided to guide incorporation of these agents into post-transplant care. Available literature was evaluated to address the clinical questions of which agents provide greatest short- and long-term benefits, timing of novel antihyperglycemic therapy initiation after transplant, monitoring parameters for these antihyperglycemic agents, and concomitant antihyperglycemic agent and immunosuppression regimen management. Current experience with novel antihyperglycemic agents is primarily limited to single-center retrospective studies and case series. With ongoing use and increasing comfort, further and more robust research promises greater understanding of the role of these agents and place in therapy for kidney transplant recipients.

New Horizons: Emerging Antidiabetic Medications

Over the past century, since the discovery of insulin, the therapeutic offer for diabetes has grown exponentially, in particular for type 2 diabetes (T2D). However, the drugs in the diabetes pipeline are even more promising because of their impressive antihyperglycemic effects coupled with remarkable weight loss. An ideal medication for T2D should target not only hyperglycemia but also insulin resistance and obesity. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and the new class of GLP1 and gastric inhibitory polypeptide dual RAs counteract 2 of these metabolic defects of T2D, hyperglycemia and obesity, with stunning results that are similar to the effects of metabolic surgery. An important role of antidiabetic medications is to reduce the risk and improve the outcome of cardiovascular diseases, including coronary artery disease and heart failure with reduced or preserved ejection fraction, as well as diabetic nephropathy, as shown by SGLT2 inhibitors. This review summarizes the main drugs currently under development for the treatment of type 1 diabetes and T2D, highlighting their strengths and side effects.

Differential Risk of Cancer Associated with Glucagon-like Peptide-1 Receptor Agonists: Analysis of Real-world Databases

BACKGROUND

Glucagon-like peptide 1 receptor agonists (GLP1Ra) are commonly used in type 2 diabetes mellitus (T2DM). However, differential risk of various cancers among GLP1Ra recipients is unknown.

METHODS

We inquired an aggregated electronic health record database, Explorys, and compared the adjusted odds ratio (aOR) of cancers between GLP1Ra and metformin users. Findings were validated in the FDA Adverse Event Reporting System (FDA FAERS).

RESULTS

From 1/2005 to 6/2019, we identified 619 340 and 64 230 patients in the metformin and GLP1Ra group, respectively. Within 5 years of starting antidiabetic medications, GLP1Ra was associated with significantly lower incident risk of prostate (aOR 0.81, p = .03), lung (aOR 0.81, p = .05), and colon cancer (aOR 0.85, p = .03), while the risk of thyroid cancer was significantly higher (aOR 1.65, p < .01). Similar findings were seen in the FDA FAERS database, where GLP1Ra was associated with lower risk of prostate (aOR 0.72, p = .08), lung (aOR 0.52, p < .01), colon cancer (aOR 0.82, p = .31), and higher risk of thyroid cancer (aOR 4.33, p < .01). In addition, with longer duration of GLP1Ra use, the risk of prostate, lung, and colon cancer further decreased, suggesting an exposure duration-response relationship.

CONCLUSIONS

GLP1Ra is associated with lower risks of prostate, lung, and colon cancer, but higher risk of thyroid cancer.

Early Intervention and Lifelong Treatment with GLP1 Receptor Agonist Liraglutide in a Wolfram Syndrome Rat Model with an Emphasis on Visual Neurodegeneration, Sensorineural Hearing Loss and Diabetic Phenotype

Wolfram syndrome (WS), also known as a DIDMOAD (diabetes insipidus, early-onset diabetes mellitus, optic nerve atrophy and deafness) is a rare autosomal disorder caused by mutations in the Wolframin1 (WFS1) gene. Previous studies have revealed that glucagon-like peptide-1 receptor agonist (GLP1 RA) are effective in delaying and restoring blood glucose control in WS animal models and patients. The GLP1 RA liraglutide has also been shown to have neuroprotective properties in aged WS rats. WS is an early-onset, chronic condition. Therefore, early diagnosis and lifelong pharmacological treatment is the best solution to control disease progression. Hence, the aim of this study was to evaluate the efficacy of the long-term liraglutide treatment on the progression of WS symptoms. For this purpose, 2-month-old WS rats were treated with liraglutide up to the age of 18 months and changes in diabetes markers, visual acuity, and hearing sensitivity were monitored over the course of the treatment period. We found that treatment with liraglutide delayed the onset of diabetes and protected against vision loss in a rat model of WS. Therefore, early diagnosis and prophylactic treatment with the liraglutide may also prove to be a promising treatment option for WS patients by increasing the quality of life.

Emerging Nondopaminergic Medications for Parkinson's Disease: Focusing on A2A Receptor Antagonists and GLP1 Receptor Agonists

Parkinson's disease (PD) is a severe neurodegenerative disease characterized by classic motor features associated with the loss of dopaminergic neurons and appearance of Lewy bodies in the substantia nigra. Due to the complexity of PD, a definitive diagnosis in the early stages and effective management of symptoms in later stages are difficult to achieve in clinical practice. Previous research has shown that colocalization of A2A receptors (A2AR) and dopamine D2 receptors (D2R) may induce an antagonistic interaction between adenosine and dopamine. Clinical trials have found that the A2AR antagonist istradefylline decreases dyskinesia in PD and could be used as an adjuvant to levodopa treatment. Meanwhile, the incretin hormone glucagon-like peptide 1 (GLP1) mainly facilitates glucose homeostasis and insulin signaling. Preclinical experiments and clinical trials of GLP1 receptor (GLP1R) agonists show that they may be effective in alleviating neuroinflammation and sustaining cellular functions in the central nervous system of patients with PD. In this review, we summarize up-to-date findings on the usefulness of A2AR antagonists and GLP1R agonists in PD management. We explain the molecular mechanisms of these medications and their interactions with other neurotransmitter receptors. Furthermore, we discuss the efficacy and limitations of A2AR antagonists and GLP1R agonists in clinical practice.

Metformin in the era of new antidiabetics

Type II diabetes mellitus is a known cardiovascular risk factor and its prevalence continues to increase. A revolution in the Type II diabetes mellitus treatment has occurred with the arrival of new antidiabetic drugs, which are thought to compromise metformin place. We aim to review the pharmacology, available evidence and clinical aspects of metformin use in the era of new antidiabetics.

Repurposing Antidiabetic Drugs for Cardiovascular Disease

Metabolic diseases and diabetes represent an increasing global challenge for human health care. As associated with a strongly elevated risk of developing atherosclerosis, kidney failure and death from myocardial infarction or stroke, the treatment of diabetes requires a more effective approach than lowering blood glucose levels. This review summarizes the evidence for the cardioprotective benefits induced by antidiabetic agents, including sodium-glucose cotransporter 2 inhibitor (SGLT2i) and glucagon-like peptide-1 receptor agonist (GLP1-RA), along with sometimes conversely discussed effects of dipeptidyl peptidase-4 inhibitor (DPP4i) and metformin in patients with high cardiovascular risk with or without type 2 diabetes. Moreover, the proposed mechanisms of the different drugs are described based on the results of preclinical studies. Recent cardiovascular outcome trials unexpectedly confirmed a beneficial effect of GLP-1RA and SGLT2i in type 2 diabetes patients with high cardiovascular risk and with standard care, which was independent of glycaemic control. These results triggered a plethora of studies to clarify the underlying mechanisms and the relevance of these effects. Taken together, the available data strongly highlight the potential of repurposing the original antidiabetics GLP1-RA and SGLT2i to improve cardiovascular outcome even in non-diabetic patients with cardiovascular diseases.

Invited review. Series: Implications of the recent CVOTs in type 2 diabetes: Which patients for GLP-1RA or SGLT-2 inhibitor?

Large cardiovascular outcome trials (CVOTs) have lent support to a cardiovascular protection with the use of SGLT2-inhibitors (SGLT2is) and GLP1-Receptor Agonists (GLP1-RAs) in subjects with type 2 diabetes. These two classes of novel glucose lowering agents have been shown to have a similar effect on the risk reduction of Major Adverse Cardiovascular Events (MACE: nonfatal myocardial infarction, nonfatal stroke, cardiovascular mortality). Nonetheless, they may not be simply interchangeable. Rather, careful evaluation of all the results of CVOTs leads identification of different effects that may allow profiling of the ideal individuals with T2DM who may benefit most from the use of one or the other class of agents. These differences include effect on heart failure, stroke and diabetic kidney disease that have prompt recent guidelines and recommendation for the treatment of type 2 diabetes to suggest the preferential use of SGLT2is in those with evidence of heart failure and impaired kidney function, while both SGLT2i and GLP1-RAs with proven effect could be use in those with prevalent atherosclerotic cardiovascular disease. This review discusses all these elements of differentiation along with others that in the future may help establishing the best cardiorenal benefit for individuals with T2DM.

Effects of liraglutide on obesity-associated functional hypogonadism in men

Lifestyle measures (LSMs) should be the first-line approach offered for obesity-related functional hypogonadism (FH). When LSMs fail, the role of testosterone replacement treatment (TRT) is unclear. GLP1 receptor agonist liraglutide is linked to progressive and sustained weight loss. A potential direct impact of GLP1 on hypothalamus-pituitary-testicular (HPT) axis was reported in animal models. We aimed to compare the effects of liraglutide and TRT on FH in obese men that had been poor responders to LSM, by means of reversal of FH and weight reduction. We designed a 16-week prospective randomized open-label study with 30 men (aged 46.5 ± 10.9 years, BMI 41.2 ± 8.4 kg/m2, mean ± s.d.) that were randomized to liraglutide 3.0 mg QD (LIRA) or 50 mg of 1% transdermal gel QD (TRT). Sexual function and anthropometric measures were assessed. Fasting blood was drawn for determination of endocrine and metabolic parameters followed by OGTT. Model-derived parameters including HOMAIR and calculated free testosterone (cFT) were calculated. Total testosterone significantly increased in both arms (+5.9 ± 7.2 in TRT vs +2.6 ± 3.5 nmol/L in LIRA) and led to improved sexual function. LIRA resulted in a significant increase of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) (P < 0.001 for between-treatment effect). Subjects treated with LIRA lost on average 7.9 ± 3.8 kg compared with a 0.9 ± 4.5 kg loss in TRT (P < 0.001). Metabolic syndrome was resolved in two patients in LIRA and in no subjects in TRT. Liraglutide was superior to TRT in improving an overall health benefit in men with obesity-associated FH after LSM failed.

Switch to Combined GLP1 Receptor Agonist Lixisenatide with Basal Insulin Glargine in Poorly Controlled T2DM Patients with Premixed Insulin Therapy: A Clinical Observation and Pilot Study in Nine Patients

INTRODUCTION

To prove the feasibility and safety of a conversion to once-daily injected GLP1 agonist (lixisenatide) and long-acting basal insulin analogue (glargine) in patients with T2DM and poorly controlled glycemia previously treated with multiple injections of premixed insulins (iPremix) in an outpatient setting.

METHODS

Nine patients with T2DM currently receiving iPremix formulations and poor glycemic control were switched to once-daily injected lixisenatide (Lixi) and basal insulin analogue glargine (iGlar) for a 12-week period. Efficacy was defined as A1c reduction of at least 0.4% and weight loss of 0.5 kg or higher.

RESULTS

Five of nine patients achieved A1c reductions of 0.4% (4 mmol/mol) or higher and six of nine patients a weight loss of 0.5 kg or higher. A mean A1C reduction of 0.5% ± 0.5% (6 mmol/mol) and mean weight loss of -1.4 ± 3.6 kg were observed in all patients. Total daily insulin dose after 12 weeks declined from 56 ± 26 IU with iPremix formulations to 47 ± 17 IU in patients taking combined iGlar and Lixi. Corrections with fast acting insulin glulisine (iGlu) were necessary in two patients on a regular basis and in four patients on an irregular basis (2.3 IU mean total daily dose). Two patients did not need additional iGlu. Postprandial glucose profiles were lower in the combined group compared with iPremix throughout the day, which resolved in the afternoon. No metabolic derangements occurred. Mild hypoglycemia and gastrointestinal symptoms were the most often reported adverse events affecting three patients.

CONCLUSION

The conversion to once-daily injected GLP1 agonist Lixi and basal iGlar could safely be performed in an outpatient setting and was associated with better postprandial glycemic control throughout the day, except dinner, compared to iPremix.

CLINICAL TRIAL REGISTRATION

EU clinical trials register EudraCT number 2013-005334-37 and ClinicalTrials.gov NCT02168491.

FUNDING

Sponsored by the Medical University of Vienna and in part supported by Sanofi-Aventis.

Real-world effectiveness and safety of dapagliflozin therapy added to a GLP1 receptor agonist in patients with type 2 diabetes

BACKGROUND AND AIM

To evaluate the effectiveness and safety of a sodium-glucose cotransporter-2 (SGLT-2) inhibitor, dapagliflozin, in patients with type 2 diabetes mellitus (T2DM) and background glucagon-like peptide-1 receptor agonist (GLP1-RA) therapy.

METHODS AND RESULTS

This is a 12-month, real-world observational study, which assessed the effectiveness and safety of dapagliflozin in patients with T2DM and background GLP1-RA therapy. The main outcome measures were changes in A1C and weight at 6 and 12 months from baseline. Secondary outcomes were differences in A1C and weight reduction between this cohort and another group of patients with T2DM treated with dapagliflozin but without background GLP1-RA therapy. In total, 109 patients with GLP1-RA and 104 patients without GLP1-RA were included. Baseline mean A1C and weight in the GLP1-RA and non-GLP1-RA groups were 7.4% vs. 7.3% and 96.2 kg vs. 95.1 kg, respectively. A significant reduction in A1C was seen with dapagliflozin in both cohorts at 6 and 12 months (GLP1-RA: -0.51% and -0.34%, non-GLP1-RA: -0.69% and -0.62%, respectively, p < 0.0001 in all analyses). Weight was significantly reduced in both groups at 6 and 12 months (GLP1-RA: -2.3 kg and -2.4 kg, non-GLP1-RA: -3.9 kg and -4.8 kg, respectively, p < 0.0001 in all analyses). A1C reduction and weight loss were significantly lower in patients with GLP1-RA than in patients without GLP1-RAs. Drug discontinuation rates were similar in both cohorts.

CONCLUSIONS

Dapagliflozin, when added in real life to patients with T2DM treated with GLP1-RAs, induced a further significant, albeit modest improvement in A1C and a further weight loss.