The sodium iodide symporter: its pathophysiological and therapeutic implications

The sodium iodide symporter (NIS) is an intrinsic plasma membrane protein that mediates the active transport of iodide in the thyroid gland and a number of extrathyroidal tissues, in particular lactating mammary gland. Because of its crucial role in the ability of thyroid follicular cells to trap iodide, cloning of NIS opened an exciting and extensive new field of thyroid-related research. Cloning and molecular characterization of NIS allowed investigation of its expression and regulation in thyroidal and nonthyroidal tissues, and its potential pathophysiological and therapeutic implications in benign and malignant thyroid disease. In addition to its key function in thyroid physiology, NIS-mediated iodide accumulation allows diagnostic thyroid scintigraphy as well as effective therapeutic application of radioiodine in benign and malignant thyroid disease. Characterization and application of NIS as a novel therapeutic gene and the presence of high native NIS expression in the majority of breast cancers further suggest a promising role of NIS in diagnosis and therapy of cancer outside the thyroid gland.

Reactivation of Dormant Relay Pathways in Injured Spinal Cord by KCC2 Manipulations

Many human spinal cord injuries are anatomically incomplete but exhibit complete paralysis. It is unknown why spared axons fail to mediate functional recovery in these cases. To investigate this, we undertook a small-molecule screen in mice with staggered bilateral hemisections in which the lumbar spinal cord is deprived of all direct brain-derived innervation, but dormant relay circuits remain. We discovered that a KCC2 agonist restored stepping ability, which could be mimicked by selective expression of KCC2, or hyperpolarizing DREADDs, in the inhibitory interneurons between and around the staggered spinal lesions. Mechanistically, these treatments transformed this injury-induced dysfunctional spinal circuit to a functional state, facilitating the relay of brain-derived commands toward the lumbar spinal cord. Thus, our results identify spinal inhibitory interneurons as a roadblock limiting the integration of descending inputs into relay circuits after injury and suggest KCC2 agonists as promising treatments for promoting functional recovery after spinal cord injury.

Sodium-Glucose Co-Transporter-2 Inhibitors and Cardiac Outcomes Among Patients Treated With Anthracyclines

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors improve outcomes among patients with established heart failure. Despite supportive basic science studies, there are no data on the value of SGLT2 inhibitors among patients treated with anthracyclines.

OBJECTIVES

This study sought to test the cardiac efficacy and overall safety of SGLT2 inhibitors in patients treated with anthracyclines.

METHODS

This study identified 3,033 patients with diabetes mellitus (DM) and cancer who were treated with anthracyclines. Cases were patients with cancer and DM who were on SGLT2 inhibitor therapy during anthracycline treatment (n = 32). Control participants (n = 96) were patients with cancer and DM who were also treated with anthracyclines, but were not on an SGLT2 inhibitor. The primary cardiac outcome was a composite of cardiac events (heart failure incidence, heart failure admissions, new cardiomyopathy [>10% decline in ejection fraction to <53%], and clinically significant arrhythmias). The primary safety outcome was overall mortality.

RESULTS

Age, sex, ethnicity, cancer type, cancer stage, and other cardiac risk factors were similar between groups. There were 20 cardiac events over a median follow-up period of 1.5 years. The cardiac event incidence was lower among case patients in comparison to control participants (3% vs 20%; P = 0.025). Case patients also experienced lower overall mortality when compared with control participants (9% vs 43%; P < 0.001) and a lower composite of sepsis and neutropenic fever (16% vs 40%; P = 0.013).

CONCLUSIONS

SGLT2 inhibitors were associated with lower rate of cardiac events among patients with cancer and DM who were treated with anthracyclines. Additionally, SGLT2 inhibitors appeared to be safe. These data support the conducting of a randomized clinical trial testing SGLT2 inhibitors in patients at high cardiac risk treated with anthracyclines.

The Na/I symporter (NIS): imaging and therapeutic applications

The Na(+)/I(-) symporter (NIS) is the plasma membrane glycoprotein that mediates the active uptake of I(-) in the thyroid, ie, the crucial first step in thyroid hormone biosynthesis. NIS also mediates I(-) uptake in other tissues, such as salivary glands, gastric mucosa, and lactating (but not nonlactating) mammary gland. The ability of thyroid cancer cells to actively transport I(-) via NIS provides a unique and effective delivery system to detect and target these cells for destruction with therapeutic doses of radioiodide. Breast cancer is the only malignancy other than thyroid cancer to have been shown to functionally express NIS endogenously. The considerable potential diagnostic and therapeutic use of radioiodide in breast cancer is currently being assessed. On the other hand, exogenous NIS gene transfer has successfully been carried out into a variety of other cell lines and tumors, including A375 human melanoma tumors, and SiHa cervix cancer, human glioma, and hepatoma cell lines. Most notably, significant radioiodine therapy results have been obtained in the NIS-transfected human prostatic adenocarcinoma cell line LNCaP and in NIS-transfected myeloma cells, both of which exhibited prolonged retention of radio iodide even in the absence of I(-) organification. The therapeutic potential of alternative NIS-transported radioisotopes with different decay properties and a shorter, physical half-life than 131I(-), such as beta-emitter 188Rhenium (188ReO(4)-) and alpha-emitter 211Astatine (211At(-)), has been evaluated. In conclusion, it is clear that the remarkable progress made in the last few years in the molecular characterization of NIS has created new opportunities for the development of diagnostic and therapeutic applications for NIS in nuclear medicine.

Quantitative molecular imaging of viral therapy for pancreatic cancer using an engineered measles virus expressing the sodium-iodide symporter reporter gene

OBJECTIVE

Our objectives were to, first, determine the oncolytic potential of an engineered measles virus expressing the sodium-iodide symporter gene (MV-NIS) for intratumoral (i.t.) therapy of pancreatic cancer and, second, evaluate NIS as a reporter gene for in vivo monitoring and quantitation of MV-NIS delivery, viral spread, and gene expression in this tumor model.

MATERIALS AND METHODS

Cultured human pancreatic cancer cells were infected with MV-NIS. Light microscopy, cell viability, and iodide uptake assays were used to confirm viral infection and NIS gene expression and function in vitro. Human pancreatic tumor xenografts were established in mice and infected via i.t. MV-NIS injections. NIS-mediated i.t. iodide uptake was quantitated by (123)I micro-SPECT/CT. i.t. MV-NIS infection was confirmed by immunohistochemistry of excised pancreatic xenografts. The oncolytic efficacy of MV-NIS was determined by measurement of tumor growth and mouse survival.

RESULTS

Infection of human pancreatic cancer cell lines with MV-NIS in vitro resulted in syncytia formation, marked iodide uptake, and ultimately cell death. Tumor xenografts infected with MV-NIS concentrated radioiodine, allowing serial quantitative imaging with (123)I micro-SPECT/CT. i.t. MV-NIS therapy of human pancreatic cancer xenografts resulted in a significant reduction in tumor volume and increased survival time of the treated mice compared with the control mice.

CONCLUSION

MV-NIS efficiently infects human pancreatic tumor cells and results in sufficient radioiodine uptake to enable noninvasive serial imaging and quantitation of the intensity, distribution, and time course of NIS gene expression. MV-NIS also shows oncolytic activity in human pancreatic cancer xenografts: Tumor growth is reduced and survival is increased in mice treated with the virus.

Sodium iodide symporter (NIS)-mediated radiovirotherapy for pancreatic cancer

OBJECTIVE

We have previously shown the therapeutic efficacy of an engineered oncolytic measles virus expressing the sodium iodide symporter reporter gene (MV-NIS) in mice with human pancreatic cancer xenografts. The goal of this study was to determine the synergy between MV-NIS-induced oncolysis and NIS-mediated (131)I radiotherapy in this tumor model.

MATERIALS AND METHODS

Subcutaneous human BxPC-3 pancreatic tumors were injected twice with MV-NIS. Viral infection, NIS expression, and intratumoral iodide uptake were quantitated with (123)I micro-SPECT/CT. Mice with MV-NIS-infected tumors were treated with 0, 37, or 74 MBq (131)I and monitored for tumor progression and survival. Additional studies were performed with stable NIS-expressing tumors (BxPC-3-NIS) treated with 0, 3.7, 18.5, 37, or 74 MBq of (131)I.

RESULTS

Mice treated with intratumoral MV-NIS exhibited significant tumor growth delay (p < 0.01) and prolonged survival (p = 0.02) compared with untreated mice. Synergy between MV-NIS-induced oncolysis and NIS-mediated (131)I ablation was not seen; however, a significant correlation was observed between NIS-mediated intratumoral iodide localization (% ID/g) and peak tumor volume reduction (p = 0.04) with combination MV-NIS and (131)I therapy. Stably transduced NIS-expressing BxPC-3 tumors exhibited rapid regression with > or = 18.5 MBq (131)I.

CONCLUSION

Delivery of (131)I radiotherapy to NIS-expressing tumors can be optimized using micro-SPECT/CT imaging guidance. Significant hurdles exist for NIS as a therapeutic gene for combined radiovirotherapy in this human pancreatic cancer model. The lack of synergy observed with MV-NIS and (131)I in this model was not due to a lack of radiosensitivity but rather to a nonuniform intratumoral distribution of MV-NIS infection.

A Preclinical Large Animal Model of Adenovirus-Mediated Expression of the Sodium–Iodide Symporter for Radioiodide Imaging and Therapy of Locally Recurrent Prostate Cancer

The sodium-iodide symporter (NIS) is primarily a thyroid protein, providing for the accumulation of iodide for biosynthesis of thyroid hormones. Native NIS expression has made possible the use of radioactive iodide to image and treat thyroid disease successfully. The current study, using adult male beagle dogs, was carried out in preparation for a Phase I clinical trial of adenovirus-mediated NIS gene (approved symbol SLC5A5) therapy for prostate cancer. Direct intraprostatic injection of virus (Ad5/CMV/NS) was followed by iv injection of 3 mCi 123I and serial image acquisition. The dogs were then given a therapeutic dose of 131I (116 mCi/m2) and observed for 7 days. SPECT/CT fusion imaging revealed clear images of the NIS-transduced prostates. Dosimetry calculations revealed an average absorbed dose to the prostate of 23 +/- 42 cGy/mCi 131I, with acceptably low radiation doses to other organs. This study demonstrated the successful introduction of localized NIS expression in the prostate gland of dogs, with no vector-related toxicity observed. None of the animals experienced any surgical complications, and serum chemistry panels showed no significant change following therapy. The results presented provide further evidence of the safety and efficacy of NIS as a therapeutic gene and support translation of this work into the clinical setting.

Repurposing sodium-glucose co-transporter 2 inhibitors (SGLT2i) for cancer treatment - A Review

Developed as an antidiabetic drug, recent evidence suggests that several sodium-glucose co-transporter 2 inhibitors (SGLT2i), especially canagliflozin and dapagliflozin, may exhibit in vitro and in vivo anticancer activities in selected cancer types, including an inhibition of tumor growth and induction of cell death. When used in combination with chemotherapy or radiotherapy, SGLT2i may offer possible synergistic effects in enhancing their treatment efficacy while alleviating associated side effects. Potential mechanisms include a reduction of glucose uptake into cancer cells, systemic glucose restriction, modulation of multiple signaling pathways, and regulation of different gene and protein expression. Furthermore, preliminary clinical findings have reported potential anticancer properties of canagliflozin and dapagliflozin in patients with liver and colon cancers respectively, with reference to decreases in their tumor marker levels. Given its general tolerability and routine use in diabetes management, SGLT2i may be a good candidate for drug repurposing in cancer treatment and as adjunct to conventional therapies. While current evidence reveals that only certain SGLT2i appear to be effective against selected cancer types, further studies are needed to explore the antitumor abilities of each SGLT2i in various cancers. Moreover, clinical trials are called for to evaluate the safety and feasibility of introducing SGLT2i in the treatment regimen of patients with specific cancers, and to identify the preferred route of drug administration for targeted delivery to selected tumor sites.

The sodium-iodide symporter

The sodium-iodide symporter (NIS) is an intrinsic plasma membrane protein that mediates active transport of iodide in the thyroid gland and several other extra-thyroidal tissues. This activity has been utilized for many years for imaging the thyroid gland and for treatment of thyroid disease both benign and malignant. Cloning and characterization of NIS has more recently allowed research into its use in non-thyroidal cancers through gene transfer for both diagnosis and treatment.

Wnt signaling regulates MFSD2A-dependent drug delivery through endothelial transcytosis in glioma

BACKGROUND

Systemic delivery of anti-tumor therapeutic agents to brain tumors is thwarted by the blood-brain barrier (BBB), an organotypic specialization of brain endothelial cells (ECs). A failure of pharmacological compounds to cross BBB is one culprit for the dismal prognosis of glioblastoma (GBM) patients. Identification of novel vascular targets to overcome the challenges posed by the BBB in tumors for GBM treatment is urgently needed.

METHODS

Temozolomide (TMZ) delivery was investigated in CT2A and PDGFB-driven RCAS/tv-a orthotopic glioma models. Transcriptome analysis was performed on ECs from murine gliomas. Mfsd2a deficient, Cav1 deficient, and Mfsd2a EC-specific inducible mice were developed to study the underlying molecular mechanisms.

RESULTS

We demonstrated that inhibiting Wnt signaling by LGK974 could increase TMZ delivery and sensitize glioma to chemotherapy in both murine glioma models. Transcriptome analysis of ECs from murine gliomas revealed that Wnt signaling inhibition enhanced vascular transcytosis as indicated by the upregulation of PLVAP and downregulation of MFSD2A. Mfsd2a deficiency in mice enhances TMZ delivery in tumors, whereas constitutive expression of Mfsd2a in ECs suppresses the enhanced TMZ delivery induced by Wnt pathway inhibition in murine glioma. In addition, Wnt signaling inhibition enhanced caveolin-1 (Cav1)-positive caveolae-mediated transcytosis in tumor ECs. Moreover, Wnt signaling inhibitor or Mfsd2a deficiency fails to enhance TMZ penetration in tumors from Cav1-deficient mice.

CONCLUSIONS

These results demonstrated that Wnt signaling regulates MFSD2A-dependent TMZ delivery through a caveolae-mediated EC transcytosis pathway. Our findings identify Wnt signaling as a promising therapeutic target to improve drug delivery for GBM treatment.

Effects of sodium-glucose co-transporter-2 inhibitors on kidney, cardiovascular, and safety outcomes in patients with advanced chronic kidney disease: a systematic review and meta-analysis of randomized controlled trials

AIMS

The overall effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors in patients with advanced chronic kidney disease (CKD) (estimated glomerular filtration rate (eGFR), 15-30 ml/min per 1.73 m²) remain unclear, and we thus conducted a systematic review and meta-analysis to evaluate the effects of SGLT2 inhibitors on kidney, cardiovascular (CV), and safety outcomes in patients with advanced CKD.

METHODS

The Medline, Embase, and Cochrane Library databases were systematically searched for randomized controlled trials (RCTs) published up to March 3, 2022, and reporting effects of SGLT2 inhibitors on kidney, CV, or safety outcomes in patients with advanced CKD.

RESULTS

From 2675 records, six RCTs with 2167 participants were included in the quantitative analyses. In patients with advanced CKD, SGLT2 inhibitors reduced the risk of the primary kidney outcome (a composite of worsening kidney function, end-stage kidney disease (ESKD), or kidney death) by 23% (RR 0.77, 95% CI 0.61-0.98, p = 0.04, I² = 0 for the heterogeneity) and slowed the annual decline in eGFR slope, with the difference between SGLT2 inhibitor group and placebo group being 1.24 mL/min/1.73m² per year (95% CI 0.06-2.42, p = 0.04). SGLT2 inhibitors were also associated with a decreased risk of primary CV outcome (a composite of CV death or hospitalization for heart failure) (HR 0.71, 95% CI 0.53-0.96, p = 0.03, I² = 0 for the heterogeneity) and with similar risks of adverse events (such as acute kidney injury, fracture, amputation, and urinary tract infection).

CONCLUSIONS

Among patients with advanced CKD, SGLT2 inhibitors reduced the risks of primary kidney and CV outcomes and attenuated the progressive decrease in eGFR compared with placebo, with no evidence of additional safety concerns. These observed benefits may support continuing the use of SGLT2 inhibitors in patients with advanced CKD before initiating maintenance dialysis or kidney transplantation. Future large-scale RCTs are needed to confirm the robustness of these results.

In vivo radioiodide imaging and treatment of pancreatic cancer xenografts after MUC1 promoter-driven expression of the human sodium-iodide symporter

INTRODUCTION AND AIMS

Mucin 1 (MUC1) is a transmembrane glycoprotein that is overexpressed in many tumor types, including breast, pancreatic, and ovarian cancer. The aim of this study was to create a construct containing sodium-iodide symporter (NIS) under the control of the 0.8-kb MUC1 promoter to infect pancreatic cancer cells both in vitro and in vivo, to investigate the potential for radioiodide imaging and ablation of this disease.

METHODOLOGY

We amplified the 797-bp MUC1 promoter by two-step nested PCR. Subsequently, a replication-deficient adenoviral construct was created containing the MUC1 promoter followed by the human NIS gene. Iodide uptake assays and immunofluorescence were used to confirm NIS expression and function. Pancreatic cancer xenografts in mice were infected with Ad/MUC1/NIS and then imaged and treated using radioiodide.

RESULTS

A 23- and 15.5-fold increase in iodide uptake was observed in Ad/MUC1/NIS-infected MUC1-positive Capan-2 and SW1990 cells with no significant increase observed in MUC1-negative Hela cells or in cells infected with the control virus. The in vivo study showed a clear image of Ad/MUC1/NIS-infected tumor xenografts using (125)I. Administration of a therapeutic dose of (131)I resulted in a regression in size to 76 +/- 15% of their original volume, whereas control tumors continued to increase in size to >200% of their original volume.

CONCLUSIONS

These results show that the 0.8-kb MUC1 promoter was successfully used to drive human NIS-targeted expression in pancreatic cancer cells, and Ad/MUC1/NIS-mediated radiotherapy can make pancreatic cancer xenografts in mice shrinking. This could potentially have applications for both imaging and therapy in other MUC1-positive tumors.

Combining a targeted radiotherapy and gene therapy approach for adenocarcinoma of prostate

A targeted radiotherapy/gene therapy approach for prostate cancer, using the radiopharmaceutical [(131)I]meta-iodobenzylguanidine ([(131)I]MIBG), would restrict the effects of radiotherapy to malignant cells, thereby increasing efficacy and decreasing morbidity of radiotherapy. Prostate cancer cells were transfected with a transgene encoding the noradrenaline transporter (NAT) under the control of tumour-specific telomerase promoters, enabling them to actively take up [(131)I]MIBG. This led to tumour-specific cell kill. This strategy has the advantage of generating a radiological bystander effect, leading to the destruction of neighbouring tumour cells that have escaped transfection. This targeted approach could be a promising tumour-specific treatment option for prostate cancer.

Changing Patterns of Antihyperglycaemic Treatment among Patients with Type 2 Diabetes in Hungary between 2015 and 2020-Nationwide Data from a Register-Based Analysis

Background and objectives: In the last couple of years, pharmacological management of patients with type 2 diabetes mellitus (T2DM) have been markedly renewed. The aim of this study was to analyse the changes in prescribing patterns of antidiabetic drugs for treating patients with T2DM in Hungary between 2015 and 2020. Material and Methods: In this retrospective, nationwide analysis, we used the central database of the National Health Insurance Fund. We present annual numbers and their proportion of T2DM patients with different treatment regimens. Results: In the period of 2015−2020, the number of incident cases decreased from 60,049 to 29,865, while prevalent cases increased from 682,274 to 752,367. Patients with metformin (MET) monotherapy had the highest prevalence (31% in 2020). Prevalence of insulin (INS) monotherapy continuously but slightly decreased from 29% to 27% while that of sulfonylurea (SU) monotherapy markedly decreased from 37% to 20%. Dipeptidyl peptidase (DPP-4) inhibitors remained popular in 2020 as monotherapy (5%), in dual combination with MET (12%) and in triple combination with MET and SU (5%). The prevalence of patients with sodium-glucose co-transporter-2 (SGLT-2) inhibitors increased from 1% to 4% in monotherapy, from <1% to 6% in dual combination with MET, and from <1% to 2% in triple oral combination with MET and SU or DPP-4-inhibitors. The prevalence of patients using glucagon-like peptide-1 receptor agonists (GLP-1-RAs) also increased but remained around 1−2% both in monotherapy and combinations. For initiating antihyperglycaemic treatment, MET monotherapy was the most frequently used regime in 2020 (50%), followed by monotherapy with SUs (16%) or INS (10%). After initial MET monotherapy, the incidence rates of patients with add-on GLP-1-RAs (2%, 3%, and 4%) and those of add-on SGLT-2 inhibitors (4%, 6%, and 8%) slowly increased in the subsequent 24, 48, and 72 months, respectively. Conclusions: In the period of 2015−2020, we documented important changes in trends of antihyperglycaemic therapeutic patterns in patients with T2DM which followed the new scientific recommendations but remained below our expectations regarding timing and magnitude. More efforts are warranted to implement new agents with cardiovascular/renal benefits into therapeutic management in time, in a much larger proportion of T2DM population, and without delay.

Sodium-glucose co-transporter 2 inhibitors in acute heart failure: real-world prescription trends and outcomes analysis

AIMS

Sodium-glucose co-transporter 2 (SGLT2) inhibitors have shown potential therapeutic benefits in heart failure (HF). However, data on their real-world usage and benefits in acute decompensated heart failure (ADHF) are limited.

METHODS AND RESULTS

We conducted a post hoc analysis of real-world data from 1108 patients with ADHF admitted to Nihon University Itabashi Hospital (Tokyo, Japan) between 2018 and 2022. Patients were divided into two groups based on the prescription of SGLT2 inhibitors during hospitalization: an SGLT2 inhibitor group (SGLT2i group) (n = 289) and a non-SGLT2i group (n = 819). The primary endpoints were death and rehospitalization for HF after discharge. The median age was 76 [interquartile range (IQR): 66, 83] years, and 732 patients (66%) were male. Data showed an increasing trend in the prescription of SGLT2 inhibitors since 2021. During a median follow-up period of 366 days (IQR: 116, 614), 458 (41.3%) patients reached the primary endpoint. The Kaplan-Meier analysis showed that the SGLT2i group had a significantly lower rate of composite events than the non-SGLT2i group, both overall (log-rank test, P < 0.001) and in the following left ventricular ejection fraction (LVEF) subgroups: HF with reduced ejection fraction (EF) (n = 413), HF with mildly reduced EF (n = 226), and HF with preserved EF (n = 466) (log-rank test; P = 0.044, P = 0.013, and P = 0.001, respectively). Furthermore, patients starting SGLT2 inhibitors during hospitalization had a significantly lower rate of composite events than those not using SGLT2 inhibitors (log-rank test, P < 0.001). This association was also significant in the LVEF subgroups (P = 0.005, P = 0.032, and P = 0.004, respectively).

CONCLUSIONS

The prescription and initiation of SGLT2 inhibitors during hospitalization are associated with improved post-discharge outcomes in patients with ADHF, irrespective of LVEF.

Systematic review and meta-analysis of head-to-head trials comparing sulfonylureas and low hypoglycaemic risk antidiabetic drugs

BACKGROUND

Safety of sulfonylurea drugs in the treatment of Type 2 Diabetes is still under debate. The aim of this study was to compare the all-cause mortality and cardiovascular adverse events of sulfonylureas and drugs with a low risk for hypoglycaemia in adults with type 2 diabetes.

METHODS

Systematic review and meta-analysis of randomised controlled trials.

DATA SOURCES

MEDLINE (PubMed, OVID), Embase, Cochrane Central Register of Controlled Trials, CINAHL, WOS and Lilacs.

STUDY SELECTION

Randomised controlled head-to-head trials that compared sulfonylureas with active control with low hypoglycaemic potential in adults (≥ 18 years old) with type 2 diabetes published up to August 2015. The drug classes involved in the analysis were metformin, dipeptidyl peptidase-4 (DPP-4) inhibitors, sodium-glucose co-transporter-2 (SGLT-2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists.

OUTCOMES

The primary endpoint was all-cause mortality. The secondary endpoints were MACE, cardiovascular events and severe hypoglycaemia.

SYNTHESIS OF RESULTS

Two reviewers checked study eligibility, independently extracted data and assessed quality with disagreements resolved through discussion. We assessed the risk of bias of the included studies using the Cochrane risk of bias tool for randomized trials v2. Pooled odds ratios (ORs) were estimated by using fixed effects model. The study is registered on PROSPERO (26/05/2016 CRD42016038780).

RESULTS

Our final analysis comprised 31 studies (26,204 patients, 11,711 patients given sulfonylureas and 14,493 given comparator drugs). In comparison to drugs with low hypoglycaemic potential, sulfonylureas had higher odds for all-cause mortality (OR 1.32, 95% CI 1.00-1.75), MACE (OR 1.32, 95% CI 1.07-1.61), myocardial infarction (fatal and non-fatal) (OR 1.67, 95% CI 1.17-2.38) and hypoglycaemia (OR 5.24, 95% CI 4.20-6.55). Subsequent sensitivity analysis revealed differences in the effect of sulfonylureas, with an increased risk of all-cause mortality with glipizide but not the other molecules.

CONCLUSION

Our meta-analysis raises concern about the safety of SUs compared to alternative drugs involved in current analysis. Important differences may exist within the drug class, and glimepiride seems to have best safety profile.

Targeted demethylation of the SLC5A7 promotor inhibits colorectal cancer progression

BACKGROUND

SLC5A7 (solute carrier family 5 member 7), also known as choline transporter 1 (CHT1), is downregulated in colorectal cancer (CRC) and functions as a tumor suppressor. However, the mechanisms underlying the inactivation of SLC5A7 in CRC remain to be elucidated.

RESULTS

In the present study, two broad-spectrum demethylation agents (azacitidine and decitabine) employed to treat CRC cells significantly upregulated SLC5A7 expression. Further results based on the CRC cohort and TCGA database indicated that SLC5A7 promoter methylation inversely correlated with SLC5A7 expression, and the status of SLC5A7 promotor methylation showed a promising prognostic value for patients with CRC. Next, the dCas9-multiGCN4/scFv-TET1CD-based precision demethylation system was constructed, which could significantly and specifically promote SLC5A7 expression in CRC cells through sgRNA targeting the SLC5A7 promoter. Both in vitro and in vivo experiments demonstrated that targeted demethylation of SLC5A7 by dCas9-multiGCN4/scFv-TET1CD-sgSLC5A7 inhibited tumor growth by stabilizing p53 and regulating downstream targets.

CONCLUSIONS

Collectively, DNA promoter methylation caused inactivation of SLC5A7 in CRC, and targeted demethylation of SLC5A7 might be a therapeutic target for CRC and other cancers.

Impact of Early Intervention with Triiodothyroacetic Acid on Peripheral and Neurodevelopmental Findings in a Boy with MCT8 Deficiency

Monocarboxylate transporter 8 (MCT8) deficiency is a rare genetic disorder characterized by peripheral thyrotoxicosis and severe cognitive and motor disability due to cerebral hypothyroidism. 3,3’,5-triiodothyroacetic acid (Triac) was shown to improve peripheral thyrotoxicosis but data on neurodevelopmental outcome are scarce. We present a case of MCT8 deficiency and the experience with Triac focusing on change in neurodevelopmental and peripheral features. A five-month-old boy was referred because of feeding difficulty, central hypotonia and global developmental delay. Despite six months of physiotherapy, physical developmental milestones did not improve, and distal muscle tone was increased. A hemizygous pathogenic variant in SLC16A2 was found and MCT8 deficiency was confirmed at 19-months. Thyroid stimulating hormone was 2.83 mIU/mL, free thyroxine 6.24 pmol/L (N=12-22) and free triiodothyronine (FT3) 15.65pmol/L (N=3.1-6.8). He had tachycardia, blood pressure and transaminases were elevated. Triac was started at 21-months. Two weeks after treatment, FT3 dramatically decreased, steady normal serum FT3 was achieved at 28-months. Assessment of neurodevelopmental milestones and signs of hyperthyroidism were evaluated at baseline, 6 months and 12 months after treatment. Signs of hyperthyroidism were improved by 6 months. Developmental composite scores of Bayley Scales of Infant Developmental 3rd Edition remained the same but important developmental milestones (head control, recognition of caregiver, response to his name) were attained, regression in the attained milestones were not observed. Initial dose, management protocol for Triac and research into its efficacy on neurodevelopmental signs in MCT8 deficiency are progressing. This case presents evidence that Triac may resolve peripheral thyrotoxicosis successfully and may slow neurodevelopmental regression, while some developmental milestones were achieved after one year of treatment.

Early treatment with a sodium-glucose co-transporter 2 inhibitor in high-risk patients with acute heart failure: Rationale for and design of the EMPA-AHF trial

AIMS

The aim of the EMPA-AHF trial is to clarify whether early initiation of a sodium-glucose co-transporter 2 inhibitor before clinical stabilization is safe and beneficial for patients with acute heart failure (AHF) who are at a high risk of adverse events.

METHODS

The EMPA-AHF trial is a randomized, double-blind, placebo-controlled, multicentre trial examining the efficacy and safety of early initiation of empagliflozin (10 mg once daily). In total, 500 patients admitted for AHF will be randomized 1:1 to either empagliflozin 10 mg daily or placebo at 47 sites in Japan. Study entry requires hospitalization for AHF with dyspnoea, signs of volume overload, elevated natriuretic peptide, and at least one of the following criteria: estimated glomerular filtration rate <60 mL/min/1.73 m²; already taking ≥40 mg of furosemide daily before hospitalization; and urine output of <300 mL within 2 hours after an adequate dose of intravenous furosemide. Patients will be randomized within 12 hours of hospital presentation, with treatment continued up to 90 days. The primary outcome is the clinical benefit of empagliflozin on the win ratio for a hierarchical composite endpoint consisting of death within 90 days, heart failure rehospitalization within 90 days, worsening heart failure during hospitalization, and urine output within 48 hours after treatment initiation.

CONCLUSION

The EMPA-AHF trial is the first to evaluate the efficacy and safety of early initiation of empagliflozin in patients with AHF considered to be at high risk under conventional treatment.

Efficacy and safety of combination of empagliflozin and metformin with combination of sitagliptin and metformin during Ramadan: an observational study

BACKGROUND

Management of diabetes during fasting is a clinical challenge. Sodium glucose co-transporter -2 inhibitors (SGLT2i) are considered safe with a low risk of hypoglycemia. However, studies on SGLT2i are scarce. This study was designed to compare the efficacy, safety, and tolerability of empagliflozin with metformin during Ramadan in comparison with sitagliptin and metformin.

METHODS

It was a prospective, observational study, conducted at 11 different sites all across Pakistan on an outpatient basis during Ramadan (May 2021-June 2021). including 132 patients, 88 who received metformin and sitagliptin, and 44 patients who received metformin and empagliflozin.

RESULTS

Patients of the SGLT-2i group experienced similar symptomatic hypoglycemic episodes (15.9%) as the sitagliptin group. There was an improvement in blood sugar levels after the use of SGLT-2i (RBS 181 ± 64 before Ramadan vs 162 ± 53 after Ramadan). HbA1c also improved after the use of SGLT-2i before and after Ramadan (7.2 ± 0.8 vs 6.9 ± 0.9 for Metformin + Empagliflozin and 7.8 ± 1.5 vs 7.6 ± 1.6 for Metformin and sitagliptin). Weight and BMI improved after the use of SGLT-2i (BMI 36.5 ± 4.8 before Ramadan and 33.7 ± 2.4 after Ramadan). There were no reported cases of urinary tract infection in the empagliflozin group.

CONCLUSION

SGLT-2 inhibitors combined with metformin for patients with diabetes during Ramadan fasting is as effective, safe and well tolerated as DPP4 combined with metformin.

Neurovascular unit disruption and blood-brain barrier leakage in MCT8 deficiency

BACKGROUND

The monocarboxylate transporter 8 (MCT8) plays a vital role in maintaining brain thyroid hormone homeostasis. This transmembrane transporter is expressed at the brain barriers, as the blood-brain barrier (BBB), and in neural cells, being the sole known thyroid hormone-specific transporter to date. Inactivating mutations in the MCT8 gene (SLC16A2) cause the Allan-Herndon-Dudley Syndrome (AHDS) or MCT8 deficiency, a rare X-linked disease characterized by delayed neurodevelopment and severe psychomotor disorders. The underlying pathophysiological mechanisms of AHDS remain unclear, and no effective treatments are available for the neurological symptoms of the disease.

METHODS

Neurovascular unit ultrastructure was studied by means of transmission electron microscopy. BBB permeability and integrity were evaluated by immunohistochemistry, non-permeable dye infiltration assays and histological staining techniques. Brain blood-vessel density was evaluated by immunofluorescence and magnetic resonance angiography. Finally, angiogenic-related factors expression was evaluated by qRT-PCR. The studies were carried out both in an MCT8 deficient subject and Mct8/Dio2KO mice, an AHDS murine model, and their respective controls.

RESULTS

Ultrastructural analysis of the BBB of Mct8/Dio2KO mice revealed significant alterations in neurovascular unit integrity and increased transcytotic flux. We also found functional alterations in the BBB permeability, as shown by an increased presence of peripheral IgG, Sodium Fluorescein and Evans Blue, along with increased brain microhemorrhages. We also observed alterations in the angiogenic process, with reduced blood vessel density in adult mice brain and altered expression of angiogenesis-related factors during brain development. Similarly, AHDS human brain samples showed increased BBB permeability to IgG and decreased blood vessel density.

CONCLUSIONS

These findings identify for the first time neurovascular alterations in the MCT8-deficient brain, including a disruption of the integrity of the BBB and alterations in the neurovascular unit ultrastructure as a new pathophysiological mechanism for AHDS. These results open a new field for potential therapeutic targets for the neurological symptoms of these patients and unveils magnetic resonance angiography as a new non-invasive in vivo technique for evaluating the progression of the disease.

Effects of sodium-glucose co-transporter-2 inhibitors by background cardiovascular medications: A systematic review and meta-analysis

AIM

To explore whether the beneficial cardiovascular (CV) effect of sodium-glucose co-transporter-2 (SGLT-2) inhibitors is consistent with or without concurrent use of CV medications in patients with type 2 diabetes, heart failure (HF) or chronic kidney disease.

METHODS

We searched Medline and Embase up to September 2022 for CV outcomes trials. The primary endpoint was the composite of cardiovascular (CV) death or hospitalization for HF. Secondary outcomes included the individual components of CV death, hospitalization for HF, death from any cause, major adverse CV events or renal events, volume depletion and hyperkalaemia. We pooled hazard ratios (HRs) and risk ratios alongside 95% confidence intervals (CIs).

RESULTS

We included 12 trials comprising 83 804 patients. SGLT-2 inhibitors reduced the risk of CV death or hospitalization for HF regardless of background use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEIs/ARBs), angiotensin receptor-neprilysin inhibitors (ARNIs), b-blockers, diuretics, mineralocorticoid receptor antagonists (MRAs), or triple combination therapy of either an ACEI/ARB plus b-blocker plus MRA, or an ARNI plus b-blocker plus MRA (HRs ranged from 0.61 to 0.83; P > .1 for each subgroup interaction). Similarly, no subgroup differences were evident for most analyses for the secondary outcomes of CV death, hospitalization for HF, all-cause mortality, major adverse CV or renal events, hyperkalaemia and volume depletion rate.

CONCLUSIONS

The benefit of SGLT-2 inhibitors seems to be additive to background use of CV medications in a broad population of patients. These findings should be interpreted as hypothesis generating because most of the subgroups analysed were not prespecified.

Sodium-Glucose Co-Transporter-2 Inhibitors in Type 1 Diabetes: A Scoping Review

BACKGROUND

With recent developments in diabetes technology, attaining adequate glucose control is more achievable than ever. Despite these improvements, a significant proportion of individuals with type 1 diabetes do not reach recommended glycaemic goals. Sodium-glucose co-transporter-2 (SGLT2) inhibitors are glucose-lowering agents that inhibit the reabsorption of filtered glucose in the kidneys, thus promoting glucosuria. Because the glucose-lowering effect of SGLT2 inhibitors is achieved independently of insulin secretion, it has been speculated whether they could bridge the gap towards achieving glycaemic targets in individuals with type 1 diabetes.

SUMMARY

Our main goal was to systematically map the current knowledge on the efficacy and safety of SGLT2 inhibitor use in adults with type 1 diabetes and present recent studies regarding the use of SGLT2 inhibitors in youth with type 1 diabetes. Using a scoping review approach, we searched MEDLINE to identify relevant clinical trials of SGLT2 inhibitors as adjunctive therapy to insulin in type 1 diabetes published from January 31, 2012, to January 31, 2022. We included the most relevant, large-scale, and long placebo-controlled clinical trials of SGLT2 inhibitors as an add-on therapy to insulin in adults with type 1 diabetes. Additionally, we included all relevant pilot studies evaluating the use of SGLT2 inhibitors as add-on therapy to insulin in youth with type 1 diabetes. We identified eight placebo-controlled clinical trials in adults with type 1 diabetes meeting our inclusion criteria and two relevant pilot studies in youth with type 1 diabetes. The clinical trials in adults with type 1 diabetes confirmed the efficacy of SGLT2 inhibitors as add-on therapy to insulin. However, this was associated with an increased incidence of diabetic ketoacidosis (DKA) versus placebo in all identified clinical trials. The two relevant pilot studies in youth with type 1 diabetes showed promising results of SGLT2 inhibitor use as an add-on therapy to insulin, especially when combined with a fully closed-loop system.

KEY MESSAGES

SGLT2 inhibitors, as an add-on therapy to insulin, improve glycaemic outcomes in adults with type 1 diabetes with a potential cost of increasing DKA risk. The use of add-on SGLT2 inhibitors to insulin shows promising results in youth with type 1 diabetes. Moreover, SGLT2 inhibitors as add-on therapy in combination with closed-loop insulin therapy could provide additional benefits in improving glycaemic control. The current role of SGLT2 inhibitors as an adjunct therapy to insulin in individuals with type 1 diabetes is yet to be determined.

Role of novel sodium glucose co-transporter-2 inhibitor enavogliflozin in type-2 diabetes: A systematic review and meta-analysis

BACKGROUND

Enavogliflozin is a novel sodium glucose co-transporter-2 inhibitor (SGLT2i) developed in South Korea. This meta-analysis was done as no meta-analysis has analysed the efficacy and safety of enavogliflozin in type-2 diabetes (T2DM).

METHODS

Electronic databases were systematically reviewed for randomized controlled trials having patients with T2DM receiving enavogliflozin in treatment-arm, and placebo/any other medicine in control-arm. Primary outcome was to evaluate changes in glycosylated haemoglobin (HbA1C). Secondary outcomes were to evaluate alterations in fasting glucose (FPG), 2-h post prandial glucose (2-h PPG), blood pressure (BP), weight, lipids, and adverse events.

RESULTS

Data from 4 trials (684 patients) was analysed for clinical outcomes over 12-24 weeks clinical use. Compared to placebo, patients receiving enavogliflozin had significantly lower HbA1c [MD -0.76%(95% CI: 0.93 to -0.60); P < 0.00001; I2 = 97%], FPG [MD -2.12 mmol/l(95%CI: 2.47 to -1.77); P < 0.00001; I2 = 91%], body-weight [MD-1.37 kgs (95% CI: 1.73-1.00); P < 0.00001; I2 = 89%], systolic BP [MD-4.99 mm Hg (95%CI: 7.83 to -2.16); P = 0.0006; I2 = 47%], diastolic BP [MD-3.09 mm Hg(95%CI: 3.38 to -2.81); P < 0.00001; I2 = 0%]. Treatment emergent adverse-events [OR1.16(95%CI:0.64-2.09); P = 0.63; I2 = 0%], serious adverse events [OR1.81(95%CI:0.37-8.83); P = 0.46; I2 = 0%], urinary infections [OR1.37(95%CI:0.09-20.61); P = 0.82; I2 = 33%] and genital infections [OR 3.07(95%CI:0.31-29.88); P = 0.33; I2 = 0%] were comparable. Compared to dapagliflozin, patients receiving enavogliflozin had significantly lower HbA1c [MD-0.06%(95%CI: 0.07-0.05); P < 0.00001; I2 = 0%], FPG [MD-0.19 mmol/l(95%CI: 0.21 to -0.17); P < 0.00001; I2 = 0%], body-weight [MD-0.20 kgs(95%CI: 0.24 to -0.15); P < 0.00001; I2 = 0%], diastolic BP [MD -0.92 mm Hg (95%CI: 1.36 to -0.48); P < 0.0001; I2 = 91%] and significantly higher urine glucose creatinine ratio [MD 16.69 g/g (95%CI:16.11-17.26); P < 0.00001; I2 = 0%].

CONCLUSION

Enavogliflozin is a well tolerated and effective SGLT2i for T2DM and may be superior to dapagliflozin with regard to certain clinical aspects over 6 months clinical use.