👤 Marcus B Jones

Internalisation of G protein-coupled receptors (GPCRs) can contribute to altered cellular responses by directing signalling from non-canonical locations, such as endosomes. If signalling processes are locally constrained, active receptors in different subcellular locations could produce different downstream effects. This phenomenon may be relevant to the optimal targeting of the glucagon-like peptide-1 receptor (GLP-1R), a type 2 diabetes and obesity target GPCR for which several ligands with varying internalisation tendency have been discovered. To investigate, we compared the signalling localisation effects of two prototypical GLP-1RAs with opposite signal bias and effects on GLP-1R trafficking: exendin-asp3 (ExD3), a full agonist that drives rapid internalisation, and exendin-phe1 (ExF1), which shows much slower internalisation. After using bioorthogonal labelling and fluorescent agonist conjugates to verify the divergent trafficking patterns of ExF1 and ExD3 in β-cell lines and primary pancreatic islets, we used live cell biosensors to monitor signalling at different subcellular locations. This revealed that cAMP/PKA/ERK signalling in β-cells is in fact distributed widely across the cell over short- (<5 min) and medium-term (up to 60 min) stimulation at pharmacological (>10 pM) concentrations, with no major differences in signal localisation that could be linked to internalised versus cell surface-bound GLP-1R. Moreover, washout experiments highlighted that, whilst fast-internalising ExD3 shows much greater accumulation and binding to GLP-1R in endosomes than slow-internalising ExF1, it is a rather inefficient driver of both cAMP production in β-cells and insulin secretion from perfused rat pancreata. These data provide a greater understanding of the cellular effects of biased GLP-1R agonism. Show less

Targeting the glucose dependent insulinotropic polypeptide receptor (GIPR) is of growing interest for treating type 2 diabetes and obesity, though the optimal approach remains unclear. Both GIPR agonism and antagonism, respectively, incorporated into drugs like tirzepatide and maridebart cafraglutide, have paradoxically both shown significant weight loss effects in humans. In this study, the metabolic impacts of a GIPR agonist (GIP108) and antagonist (NN-GIPR-Ant) were evaluated in lean and high-fat diet (HFD)-induced obese male mice. We assessed the impacts on food intake, body weight, glucose and insulin tolerance, liver triglyceride levels, bone markers and adipose tissue lipolytic gene expression. In lean mice, neither peptide affected food intake or body weight, but GIP108 improved glucose tolerance. In obese mice, both agents reduced food intake and body weight, with NN-GIPR-Ant producing more sustained appetite suppression. Energy expenditure remained unchanged, as weight loss matched that of pair-fed controls. GIP108 improved glucose tolerance independently of weight loss, whereas NN-GIPR-Ant reduced insulin sensitivity compared to pair-fed controls. Both treatments slightly increased liver triglyceride content compared to their pair-fed controls, and no treatment significantly affected plasma bone marker levels. Finally, NN-GIPR-Ant reduced the expression of adipose tissue lipolytic genes. Our data highlights the distinct metabolic effects of GIPR agonism and antagonism, offering insights for their future application in personalised metabolic disease treatments. Further human studies are needed to understand the long-term metabolic impacts of these therapies. Show less

Neuritin 1 (NRN1) has emerged as a multifaceted regulator of synaptic plasticity, neuronal excitability and structural remodelling. This review synthesises knowledge of NRN1 function across the central and peripheral nervous systems, with a focus on its roles in sensory neurones and neuronal repair following injury. We discuss evidence that NRN1 interacts with classical neurotrophic pathways, including brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), while engaging distinct cellular mechanisms that span activity-dependent trafficking, modulation of calcium and potassium channel function and regulated local axonal mRNA translation. Accumulating data indicate that NRN1 contributes to injury-induced plasticity and functional recovery through both cell-autonomous neuronal mechanisms and non-cell-autonomous signalling involving glial and stromal cells. In long-projecting sensory axons, regulated transport and local translation of Nrn1 mRNA position NRN1 as a spatially restricted effector of axonal growth, excitability and regeneration. Dysregulation of NRN1 expression and signalling has been implicated in pathological contexts including neurodegeneration, diabetic peripheral neuropathy and inflammatory pain, where restoration of NRN1 activity promotes axonal integrity, Schwann cell survival and neurotrophic support. Beyond neurons, NRN1 also modulates inflammatory and angiogenic pathways, including VEGF and CXCR4 signalling, linking neuronal plasticity to broader tissue and immune responses. Together, these findings support a model in which NRN1 acts as a molecular integrator of neurotrophic, metabolic and injury-associated signals, coordinating plasticity while also presenting potential routes to maladaptive sensitisation. We highlight key mechanistic and translational challenges that must be addressed to harness NRN1 biology therapeutically aimed at enhancing neuronal repair while limiting persistent sensory dysfunction. Show less

Treatment failures in rheumatoid arthritis (RA) leads to undesirable morbidity associated with immunosuppression. Recent studies of synovial tissue from refractory RA patients highlight the role of synovial fibroblasts and vascular endothelium in driving treatment failure. Utilizing high-dimensional spatial transcriptomics, we uncovered a crucial role for neurotrophin signaling in driving abnormal vascular maturation in RA synovia. Neurotrophins, including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT3), induce differentiation of synovial fibroblasts into mural cells - pericytes and vascular smooth muscle cells. Mechanistically, NOTCH3 signaling activates a cascade of neurotrophin signaling through transcriptional induction of NGFR, a co-receptor for NGF. In RA synovial tissue explants, stimulation with NGF, BDNF, or NT3 leads to a dramatic increase in maturation of synovial tissue vasculature. Conversely, pharmacologic inhibition with neurotrophin inhibitors drastically abolished maturation of vascularization in RA synovial explants. Notably, the FDA-approved tropomyosin receptor kinase (TRK) inhibitors larotrectinib and entrectinib effectively reverse synovial vascular maturation in human RA tissue explants.Our findings suggest that fibroblast-derived neurotrophin signaling is a critical pathway in sustaining mature blood vessels in RA synovia, and that neurotrophin inhibitors reverse abnormal vascular maturation in RA. In rheumatoid arthritis, fibroblast neurotrophin signaling drives abnormal vascular maturation by inducing differentiation of fibroblasts into vascular mural cells. Show less

A single session of vagus nerve stimulation (VNS) has been shown to improve cognition in male rodents, but the influence of sex on the effects of VNS on behavior and synaptic plasticity are poorly understood. The present study investigated cognitive performance and hippocampal (HC) electrophysiology/brain derived neurotrophic factor (BDNF) expression in female healthy adult rats to examine changes in cognition and synaptic plasticity after VNS paired training. A total of 44 female rats were utilized for the cognitive neurobehavior experiments and a total of 68 female rats were utilized for the electrophysiology experiments. Animals were divided into four groups: SHAM in diestrus (SHAM-D), SHAM in estrus (SHAM-E), VNS in diestrus (VNS-D), and VNS in estrus (VNS-E). Electrode wires were surgically implanted around the left cervical vagus nerve (VN) prior to stimulation and experimentation in female Sprague–Dawley rats. A single 30 min session of VNS (100 µs biphasic pulses, 30 Hz, 0.8 mA) was administered after neurobehavior training in a Novel Object Recognition (NOR) and a Passive Avoidance Task (PAT) and testing was performed 24 h after VNS. Electrophysiology recordings for input/output, long-term potentiation, spontaneous spiking, and paired-pulse facilitation (PPF) were collected 90 min after VNS to assess the functional effects of VNS on HC slices. Immunohistochemistry (IHC) was conducted on HC slices collected 48 h after VNS to quantify HC subregion specific changes in BDNF. Stimulated rats exhibited improved performance in the PAT when tested in the diestrus phase. Among all subjects, VNS increased response amplitude and decreased PPF. However, among those in diestrus VNS increased long-term potentiation (LTP) amplitude and frequency of spontaneous spiking, and decreased PPF in the CA1. Among those in estrus, VNS did not change LTP amplitude or PPF, but frequency of spontaneous spiking was increased. VNS and estrous cycle stage additionally influenced the HC expression of BDNF in the CA1 and CA2. These findings suggest that a single session of VNS can increase synaptic plasticity, but that an interaction between estrous cycle phase and VNS influences the effects of VNS in females. This study is among the first to investigate the influence of estrous cycle phase on cognitive neurobehavior and synaptic plasticity outcomes after VNS and contributes to the understanding of VNS-induced cognitive enhancement. The online version contains supplementary material available at 10.1186/s42234-025-00196-3. Show less

High-density and low-density lipoproteins (HDL and LDL) are established analytical targets for diagnosis and risk stratification of numerous chronic diseases. This study investigates potential sources of bias in lipoprotein particle counting (HDL-P and LDL-P), focusing on the most atheroprotective small-HDL and most pro-atherogenic small-LDL. Plasma samples were fractionated using asymmetric-flow field-flow fractionation (AF4), coupled with hydrodynamic size measurement and comprehensive liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of each fraction. Concentration-size profiles were deconvoluted into 10 HDL and 8 LDL Gaussian subspecies. Molecular volume ratios were used to evaluate proposed particle models, providing evidence for the presence of s-HDL disk and s-LDL dimers, as sources of bias in calculated HDL-P and LDL-P when spherical particle geometry is assumed. Matching apoA1/HDL-P and apoB/LDL-P to consensus values enabled correction of mass diameters (k*d Show less

Elevated atherogenic lipoproteins increase risk of atherosclerotic cardiovascular disease (ASCVD), though long-term risk for adults without ASCVD who have low-normal levels has not been well described. This study used pooled data from 16,384 individuals in 3 population-based prospective cohorts. At baseline all participants were without ASCVD and were not taking lipid-lowering therapy. We evaluated ASCVD events by baseline LDL-C, non-HDL-C and apoB, including low-normal values. ASCVD risk was assessed using multivariable Cox proportional hazards. The study cohort had a mean age of 52 (SD 18) years with 56.5% women, 64.7% of White race and 35.3% of Black race. Over a median follow-up of 18.8 years, unadjusted ASCVD event incidence was similar for adults with baseline LDL-C < 70 mg/dL and 70 to 99 mg/dL, and higher with LDL-C ≥ 100 mg/dL; trends were similar for non-HDL-C and apoB categories. Compared to having baseline LDL-C 70 to 99 mg/dL, LDL-C < 70 mg/dL was associated with similar ASCVD risk (adjusted HR 1.16 [95% Confidence Interval, 95% CI 0.90-1.50]) and LDL-C ≥ 130 mg/dL was associated with higher risk (adjusted HR 1.31 [95% CI 1.14-1.50]) after multivariable adjustment; adults with non-HDL-C ≥ 160 mg/dL or apoB ≥ 90 mg/dL also had higher risk after multivariable adjustment. Among adults without ASCVD not taking lipid-lowering therapy at baseline, ASCVD risk for adults with low-normal and high-normal LDL-C, non-HDL-C and apoB was similar, and their risk remained less than in adults with elevated lipoproteins. These findings emphasize the importance of achieving normal atherogenic lipoprotein levels for primary prevention of ASCVD from early adulthood through middle age. Show less

The full impact of APOE4 (apolipoprotein E4), the strongest genetic risk factor for Alzheimer's disease (AD), on neuronal and network function remains unclear, particularly during early preclinical stages of disease. Here we show that young APOE4 knockin (E4-KI) mice exhibit hippocampal region-specific network hyperexcitability that predicts later cognitive deficits. This early phenotype arises from cell-type-specific subpopulations of smaller, hyperexcitable neurons and is eliminated by selective removal of neuronal APOE4. With aging, E4-KI mice develop granule cell hyperexcitability, progressive inhibitory dysfunction and excitation-inhibition imbalance in the dentate gyrus. Single-nucleus RNA sequencing with multilevel gene filtering reveals age-dependent and cell-type-specific transcriptional changes and identifies candidate mediators of early neuronal hyperexcitability, including Nell2. Targeted CRISPR interference knockdown of Nell2 rescues abnormal excitability, implicating Nell2 as a contributor to APOE4-driven dysfunction. Together, these findings define molecular and circuit mechanisms linking neuronal APOE4-induced early network impairment to AD pathogenesis with aging. Show less

Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. Unfortunately, the early stages of this disease are poorly understood, which has led to limited treatment options. Investigating normal changes in tissues eventually affected by AMD can further elucidate the mechanisms of disease progression and lead to novel therapeutic targets. The primary cell layer affected in AMD is the retinal pigment epithelium (RPE), which forms the outer blood-retinal barrier (oBRB). Beneath the RPE lies Bruch's membrane, a proteinaceous layer that naturally thickens and stiffens with age. These changes to Bruch's membrane are also implicated in RPE dysfunction and AMD progression. To investigate the relationship between normal, age-related changes in Bruch's membrane and AMD development, we engineered a tunable in vitro model of Bruch's membrane to support primary porcine RPE cells. We performed transepithelial electrical resistance (TEER) measurements, viability assays, morphological analysis, immunocytochemistry, and enzyme-linked immunosorbent assays (ELISA) to evaluate monolayer integrity and angiogenic factor expression. Cells cultured on our aged model exhibited changes similar to those seen in AMD, including reduced monolayer integrity, the formation of sub-RPE deposits, and eventual cell death. Notably, apolipoprotein E (ApoE), a known drusen component and Alzheimer's disease marker, was overexpressed prior to deposit accumulation and cell death. Regions of ApoE overexpression corresponded with disrupted expression of zonula occludens-1, a junctional protein. While most angiogenic factors remained unchanged, tissue inhibitor of metalloproteinases-1 (TIMP-1) was transiently overexpressed before cell death. These findings suggest that ApoE and TIMP-1 may play key roles in early AMD pathogenesis and represent potential targets for future therapeutic intervention. Show less

The genetic basis of sporadic early-onset Alzheimer's disease (EOAD) remains largely unknown, prompting evaluation of late-onset Alzheimer's disease (LOAD) polygenic risk in EOAD. A LOAD polygenic score (PGS) was calculated in the Longitudinal Early-onset Alzheimer's Disease Study (LEADS) and Alzheimer's Disease Neuroimaging Initiative (ADNI) study and tested for associations with AD risk, cognitive performance, and imaging and fluid biomarkers. Though PGS was elevated in LOAD and EOAD, it was not a significant predictor of EOAD adjusting for APOE ε4 carrier status and was not associated with age of EOAD onset (p = 0.106) or with cognitive performance (p = 0.417). In LEADS, greater LOAD PGS was associated with differences in neuroimaging and fluid biomarkers, including elevated synaptosomal-associated protein 25 (SNAP-25) (p = 2.3 × 10 While LOAD polygenic risk contributed minimally to EOAD onset and cognitive dysfunction, PGS association with fluid biomarkers in LEADS suggests a role for LOAD polygenic risk in EOAD pathophysiology. LOAD PGSs were elevated in both LOAD and EOAD compared to controls; however, LOAD PGS did not significantly predict EOAD risk, age at onset, or cognitive performance independent of APOE ε4 in the LEADS. Higher LOAD PGS was associated with lower amyloid PET Centiloids (less brain amyloid deposition) as well as lower CSF biomarker Aβ42 in LEADS (proxy marker suggesting higher brain amyloid deposition) in LEADS; these contradictory findings support the need for larger studies to further investigate whether LOAD PGS is associated with increased amyloid deposition in EOAD. Higher LOAD PGS was also associated with higher levels of CSF synaptosomal-associated protein 25 (SNAP-25), a key component of the SNARE complex, suggesting that LOAD genetic factors may contribute to dysregulation of synaptic transmission and/or pathological protein aggregation in EOAD. Show less

Lecanemab is an anti-amyloid monoclonal antibody, recently approved in the UK as a treatment for mild cognitive impairment (MCI) and mild dementia due to Alzheimer's disease (AD) in adults who are apolipoprotein E ε4 gene ( Show less

Neuronal ceroid lipofuscinosis type 3 (CLN3) disease is a rare, life-limiting pediatric neurodegenerative disorder with no approved disease-modifying therapy. We conducted a prospective case report from October 2023 to April 2025 involving two female siblings with genetically confirmed CLN3 disease (homozygous for the common 1 kb deletion). Both patients were treated with oral, weight-based miglustat for 18 months. Miglustat was supplied as off-label use in the absence of a therapeutic alternative for this severe neurodegenerative disorder. Clinical outcomes were assessed using comprehensive ophthalmologic evaluation, the Unified Batten Disease Rating Scale (UBDRS), and the Vineland Adaptive Behavior Scales, Third Edition (Vineland-3). At the time of report, patients were aged 13 and 10 years. Both had been diagnosed at age 7 years and commenced miglustat at ages 11 and 9 years, respectively. Over the treatment period, both patients demonstrated improvement in visual acuity and clinical stabilization on the Unified Batten Disease Rating Scale. One patient showed measurable improvement in adaptive functioning as assessed by Vineland-3. No significant adverse effects were reported. These preliminary findings suggest potential short-term clinical benefit of miglustat in pediatric patients with CLN3 disease, particularly when initiated early in the disease course. Further studies involving larger cohorts and longer follow-up are warranted to evaluate the safety and long-term efficacy of miglustat in this population. Show less

Acute myeloid leukemia (AML) is a complex hematologic malignancy with multiple disease subgroups defined by somatic mutations and heterogeneous outcomes. Although genome-wide association studies (GWAS) have identified a small number of common genetic variants influencing AML risk, the heritable component of this disease outside of familial susceptibility remains largely undefined. Here, we perform a meta-analysis of 4 published GWAS plus 2 new GWAS, totaling 4710 AML cases and 12 938 controls. We identify a new genome-wide significant risk locus for pan-AML at 2p23.3 (rs4665765; P = 1.35 × 10-8; EFR3B, POMC, DNMT3A, and DNAJC27), which also significantly associates with patient survival (P = 6.09 × 10-3). Our analysis also identifies 3 new genome-wide significant risk loci for disease subgroups, including AML with deletions of chromosome 5 and/or 7 at 1q23.3 (rs12078864; P = 7.0 × 10-10; DUSP23) and cytogenetically complex AML at 2q33.3 (rs12988876; P = 3.28 × 10-8; PARD3B) and 2p21 (rs79918355; P = 1.60 × 10-9; EPCAM). We also investigated loci previously associated with the risk of clonal hematopoiesis (CH) or CH of indeterminate potential and identified several variants associated with the risk of AML. Our results further inform on AML etiology and demonstrate the existence of disease subgroup specific risk loci. Show less

Infiltration of T cell acute lymphoblastic leukemia (T-ALL) into the meninges worsens prognosis, underscoring the need to understand mechanisms driving meningeal involvement. Here, we show that T-ALL cells expressing CXCR3 exploit normal T cell function to infiltrate the inflamed meninges. CXCR3 deletion hampered disease progression and extramedullary dissemination by reducing leukemic cell proliferation and migration. Conversely, forced expression of CXCR3 facilitated T-ALL trafficking to the meninges. We identified the ubiquitin-specific protease 7 as a key regulator of CXCR3 protein stability in T-ALL. Furthermore, we discovered elevated levels of CXCL10, a CXCR3 ligand, in the cerebrospinal fluid from patients with T-ALL and leukemia-bearing mice. Our studies demonstrate that meningeal stromal cells, specifically pericytes and fibroblasts, induce CXCL10 expression in response to leukemia and that loss of CXCL10 attenuated T-ALL influx into the meninges. Moreover, we report that leukemia-derived proinflammatory cytokines, TNF-α, IL-27, and IFN-γ, induced CXCL10 in the meningeal stroma. Pharmacological inhibition or deletion of CXCR3 or CXCL10 reduced T-ALL cell migration and adhesion to meningeal stromal cells. Finally, we reveal that CXCR3 and CXCL10 upregulated VLA-4/VCAM-1 signaling, promoting cell-cell adhesion and thus T-ALL retention in the meninges. Our findings highlight the pivotal role of CXCR3-CXCL10 signaling in T-ALL progression and meningeal colonization. Show less

Lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease. Although Lp(a) levels are generally stable, the extent of intraindividual variation and the need for repeat Lp(a) testing remain unclear. To evaluate the intraindividual variation in Lp(a) levels assess the clinical impact of repeat testing on cardiovascular risk classification. This retrospective study analyzed 250 patients from a tertiary care lipid clinic with ≥2 Lp(a) measurements over a mean of 17.1 ± 15.5 months. Baseline levels were positively skewed (median of 56.0 nmol/L; interquartile range 21.0-154.3 nmol/L). Intraindividual coefficients of variation (CV) were 19.0% (mean-based) and 33.6% (log-transformed), exceeding the European Federation of Clinical Chemistry and Laboratory Medicine database CV (10.2%; 4.3%-26.7%). Cardiovascular risk reclassification occurred for 12.4% using the National Lipid Association thresholds (75 and 125 nmol/L) and 6.8% using the European Society of Cardiology threshold (105 nmol/L). Variability was not associated with time between measurements, medications, or biochemical parameters on multivariable analysis. Hence, repeat Lp(a) testing is generally unnecessary but could be considered in those near risk thresholds or those being evaluated for Lp(a)-lowering therapies. Show less

This study used compositional data techniques that address the interdependence of 24-h movement behaviors (sleep, sedentary behavior [SB], light-intensity physical activity [LPA], moderate-to-vigorous intensity physical activity [MVPA]) to examine: (1) how patients undergoing metabolic bariatric surgery (MBS) allocate time among these behaviors before MBS, and (2) whether overall time-use composition and modeled reallocation patterns relate to early weight loss after MBS. Participants wore an accelerometer 24 h/day for 10 days before MBS to measure time in sleep, SB, LPA, and MVPA. Isotemporal substitution models estimated differences in 6-month post-MBS percentage total weight loss (%TWL) associated with reallocations of these pre-surgery movement behaviors. Forty-five participants provided valid data. Pre-MBS time-use composition was associated with %TWL (23.8 ± 5.1%; F = 2.66, p = 0.047). Reallocating 15-60 SB or LPA minutes/day to MVPA was estimated to relate to 0.9-3.5% greater %TWL. Reallocating 15-30 MVPA minutes/day to SB or LPA was estimated to relate to 1.4-5.0% less %TWL (all comparisons p < 0.05). Other reallocations were non-significant. In conclusion, modeled shifts in time from SB or LPA to MVPA and vice versa were associated with estimated increases or decreases in early post-surgical weight loss, respectively. Experimental research is needed to clarify causal relationships and inform interventions to improve MBS outcomes. Show less

To delineate organ-specific and systemic drivers of metabolic dysfunction-associated steatotic liver disease (MASLD), we applied integrative causal inference across clinical, imaging, and proteomic domains in individuals with and without type 2 diabetes (T2D). Bayesian network analyses and complementary two-sample Mendelian randomization were used to quantify causal pathways linking adipose distribution, glycemia, and insulin dynamics with liver fat in the IMI-DIRECT prospective cohort study. Data included frequently sampled metabolic challenge tests, MRI-derived abdominal and hepatic fat content, serological biomarkers, and Olink plasma proteomics from 331 adults with new-onset T2D and 964 adults without diabetes, with harmonized protocols enabling replication. High basal insulin secretion rate (BasalISR), estimated via C-peptide deconvolution, emerged as the primary potential causal driver of liver fat accumulation in both cohorts. BasalISR, a clearance-independent measure of β-cell insulin output distinct from peripheral insulin levels, was independently linked to hepatic steatosis. Visceral adipose tissue exhibited bidirectional associations with liver fat, suggesting a self-reinforcing metabolic loop. Of 446 analyzed proteins, 34 mapped to these metabolic networks (27 in the non-diabetes network, 18 in the T2D network, and 11 shared). Key proteins directly associated with liver fat included GUSB, ALDH1A1, LPL, IGFBP1/2, CTSD, HMOX1, FGF21, AGRP, and ACE2. Sex-stratified analyses identified GUSB in females and LEP in males as the strongest protein predictors of liver fat. BasalISR may better capture early β-cell-driven disturbances contributing to MASLD. These findings outline a multifactorial, sex- and disease stage-specific proteo-metabolic architecture of hepatic steatosis and identify potential biomarkers or therapeutic targets. Show less

The use of incretin analogues has emerged as an effective approach to achieve both enhanced insulin secretion and weight loss in Type 2 diabetes (T2D) patients. Agonists which bind and stimulate multiple receptors have shown particular promise. However, off-target effects remain a complication of using these agents, and modified versions with optimised pharmacological profiles and/or biased signalling are sought. Ligand synthesis was achieved using standard solid-phase techniques. Assessments of GLP-1R-binding kinetics, G protein recruitment and receptor internalisation were performed using biochemical and imaging approaches. Insulin secretion was measured in purified mouse and human islets, and drug efficacy was assessed in hyperglycaemic db/db mice. We describe the synthesis and properties of a molecule which binds to both glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors (GLP-1R and GIPR) to enhance insulin secretion. HISHS-2001 shows increased affinity at the GLP-1R, as well as a tendency towards reduced internalisation and recycling at this receptor versus FDA-approved dual GLP-1R/GIPR agonist tirzepatide. HISHS-2001 also displayed significantly greater bias towards cAMP generation versus β-arrestin 2 recruitment compared to tirzepatide. In contrast, G HISHS-2001 represents a novel dual receptor agonist with a promising pharmacological profile and actions. Future clinical studies will be needed to assess the safety and efficacy of this molecule in humans. Show less

Dual agonists targeting glucagon-like peptide-1 receptor (GLP1R) and glucose-dependent insulinotropic polypeptide receptor (GIPR) are breakthrough treatments for patients with type 2 diabetes and obesity. Compared to GLP1R agonists, dual agonists show superior efficacy for glucose lowering and weight reduction. However, delineation of dual agonist cell targets remains challenging. Here, we develop and test daLUXendin and daLUXendin+, non-lipidated and lipidated fluorescent GLP1R/GIPR dual agonist probes, and use them to visualize cellular targets. daLUXendins are potent GLP1R/GIPR dual agonists that advantageously show less functional selectivity for mouse GLP1R over mouse GIPR. daLUXendins label rodent and human pancreatic islet cells, with a signal intensity of β cells > α cells = δ cells. Systemic administration of daLUXendin strongly labels GLP1R Show less

The use of incretin analogues has emerged in recent years as an effective approach to achieve both enhanced insulin secretion and weight loss in type 2 diabetes (T2D) patients. Agonists which bind and stimulate multiple receptors have shown particular promise. However, off target effects, including nausea and diarrhoea, remain a complication of using these agents, and modified versions with optimized pharmacological profiles and/or biased signaling at the cognate receptors are increasingly sought. Here, we describe the synthesis and properties of a molecule which binds to both glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors (GLP-1R and GIPR) to enhance insulin secretion. HISHS-2001 shows increased affinity at the GLP-1R, as well as a tendency towards reduced internalization and recycling at this receptor Show less

There is renewed interest in targeting the glucose-dependent insulinotropic polypeptide receptor (GIPR) for treatment of obesity and type 2 diabetes. G-protein coupled receptor desensitisation is suggested to reduce the long-term efficacy of glucagon-like-peptide 1 receptor (GLP-1R) agonists and may similarly affect the efficacy of GIPR agonists. We explored the extent of pancreatic GIPR functional desensitisation with sustained agonist exposure. A long-acting GIPR agonist, GIP108, was used to probe the effect of sustained agonist exposure on cAMP responses in dispersed pancreatic islets using live cell imaging, with rechallenge cAMP responses after prior agonist treatment used to quantify functional desensitisation. Receptor internalisation and β-arrestin-2 activation were investigated in vitro using imaging-based assays. Pancreatic mouse GIPR desensitisation was assessed in vivo via intraperitoneal glucose tolerance testing. GIP108 treatment led to weight loss and improved glucose homeostasis in mice. Prolonged exposure to GIPR agonists produced homologous functional GIPR desensitisation in isolated islets. GIP108 pre-treatment in vivo also reduced the subsequent anti-hyperglycaemic response to GIP re-challenge. GIPR showed minimal agonist-induced internalisation or β-arrestin-2 activation. Although GIP108 chronic treatment improved glucose tolerance, it also resulted in partial desensitisation of the pancreatic islet GIPR. This suggests that ligands with reduced desensitisation tendency might lead to improved in vivo efficacy. Understanding whether pancreatic GIPR desensitisation affects the long-term benefits of GIPR agonists in humans is vital to design effective metabolic pharmacotherapies. Show less

Post-labelling cleavable substrates for self-labelling protein tags, such as SNAP- and Halo-tags, can be used to study cell surface receptor trafficking events by stripping dyes from non-internalized protein pools. Since the complexity of receptor biology requires the use of multiple and orthogonal approaches to simultaneously probe multiple receptor pools, we report the development of four membrane impermeable probes that covalently bind to either the SNAP- or the Halo-tag in the red to far-red range. These molecules bear a disulfide bond to release the non-internalized probe using the reducing agent sodium 2-mercaptoethane sulfonate (MESNA). As such, our approach allows the simultaneous visualization of multiple internalized cell surface proteins in two colors which we showcase using G protein-coupled receptors. We use this approach to detect internalized group II metabotropic glutamate receptor (mGluRs), homo- and heterodimers, and to reveal unidirectional crosstalk between co-expressed glucagon-like peptide 1 (GLP1R) and glucose-dependent insulinotropic polypeptide receptors (GIPR). In these applications, we translate our method to both high resolution imaging and quantitative, high throughput assays, demonstrating the value of our approach for a wide range of applications. Show less

Deep Mutational Scanning (DMS) is an emerging method to systematically test the functional consequences of thousands of sequence changes to a protein target in a single experiment. Because of its utility in interpreting both human variant effects and protein structure-function relationships, it holds substantial promise to improve drug discovery and clinical development. However, applications in this domain require improved experimental and analytical methods. To address this need, we report novel DMS methods to precisely and quantitatively interrogate disease-relevant mechanisms, protein-ligand interactions, and assess predicted response to drug treatment. Using these methods, we performed a DMS of the melanocortin-4 receptor (MC4R), a G-protein-coupled receptor (GPCR) implicated in obesity and an active target of drug development efforts. We assessed the effects of >6600 single amino acid substitutions on MC4R's function across 18 distinct experimental conditions, resulting in >20 million unique measurements. From this, we identified variants that have unique effects on MC4R-mediated Gα Show less

This study investigates how sorafenib induces toxicity in glomerular cells and examines the protective role of 8,9-epoxyeicosatrienoic acid (8,9-EET) analogs in reducing this kidney damage. Human renal mesangial cells (HRMCs) and podocytes were treated with no treatment, sorafenib alone, or sorafenib combined with 8,9-EET analogs. Cell viability and apoptosis were measured in both cell types. Sorafenib (1-10 µM) lowered cell viability and increased caspase 3/7 activity in a dose-dependent way in HRMCs and podocytes. Five of twenty 8,9-EET analogs significantly enhanced cell survival and decreased apoptosis. RNA sequencing showed that sorafenib altered 1244 genes, including those involved in cell cycle and the Raf/MEK/ERK pathway. The 8,9-EET analog MDB-52a raised ANGPTL4 levels, linked to metabolism and vascular health, and reduced ACTA2, which could activate protective pathways. Nephroseq data correlated these gene changes with glomerulosclerosis. MDB-52 appears to counteract gene disruptions and protect against sorafenib-induced kidney damage. Overall, 8,9-EET analogs targeting glomerular cells could be potential therapeutic agents to lessen sorafenib-related nephrotoxicity. Show less

Cirrhosis and hepatocellular carcinoma (HCC) are long-term complications of chronic liver disease (CLD). In this large multi-ancestry genome-wide association study of all-cause cirrhosis (35,481 cases, 2.36M controls) and HCC (6,680 cases, 1.76M controls), we identified 27 loci associated with cirrhosis (10 novel) and 11 with HCC (three novel). Three novel cirrhosis loci were replicated in independent cohorts (e.g. Show less

The peri- and early post-infarction period carries an increased risk of recurrent ischemic events. Oxidized phospholipids (OxPLs) are pro-inflammatory and contribute to plaque instability and thrombosis. This study aimed to: (1) assess changes, during the early post-MI period in OxPL-apo(a) and OxPL-apoB, (2) evaluate the effect of PCSK9 inhibition on these changes, and (3) explore their relationships with the changes in Lp(a) and LDL-C. Ninety-six participants with NSTEMI or STEMI were randomized to receive placebo (n = 48) or 420 mg subcutaneous evolocumab (n = 48) within 24 h of admission. OxPL-apo(a), OxPL-apoB, Lp(a), and LDL-C levels were measured at baseline and 30 days post-MI. In the placebo group, OxPL-apo(a) increased from 52.6 [19.3, 106.5] nmol/L at baseline to 61.7 [31.5, 116.9] nmol/L at 30 days (p = 0.014), and OxPL-apoB rose from 6.7 [3.1, 21] nmol/L to 8.8 [3.7, 23] nmol/L (p = 0.0045). In contrast, no significant changes were observed for OxPL-apo(a) (p = 0.17) or OxPL-apoB (p = 0.058) in the evolocumab group. OxPL-apo(a) correlated strongly with Lp(a) at baseline (r = 0.93, p < 0.001) and 30 days (r = 0.94, p < 0.001), and OxPL-apoB correlated similarly (baseline: r = 0.92, p < 0.001; 30 days: r = 0.93, p < 0.001). No correlation was observed between OxPLs and LDL-C. OxPL-apo(a) and OxPL-apoB levels were strongly correlated with Lp(a) and increased during the early post-infarction period. This increase was prevented by in-hospital administration of a PCSK9 inhibitor. These findings provide new insights into early changes in OxPLs following acute MI and suggest a protective role for PCSK9 inhibition during this critical period. Show less

Mixed dyslipidaemia, characterised by elevated concentrations of circulating triglycerides and LDL cholesterol (LDL-C), is associated with an increased risk of atherosclerotic cardiovascular disease. Solbinsiran, a GalNAc-conjugated small interfering RNA targeting hepatic angiopoietin-like protein 3 (ANGPTL3), reduced triglycerides and LDL-C concentrations in a phase 1 study. This study aimed to assess the durability and efficacy of solbinsiran in reducing concentrations of atherogenic lipoproteins in adults with mixed dyslipidaemia. This double-blind, parallel-arm, randomised, placebo-controlled, phase 2 trial enrolled adults (aged ≥18 years) with mixed dyslipidaemia at 41 clinical research units across seven countries. Patients receiving moderate-intensity or high-intensity statins, and with concentrations of fasting triglycerides between 1·69 mmol/L and 5·64 mmol/L, LDL-C of at least 1·81 mmol/L, and non-HDL cholesterol of at least 3·36 mmol/L were included. Using an interactive web-response system, patients were randomly assigned (1:2:2:2) to receive either solbinsiran 100 mg, solbinsiran 400 mg, solbinsiran 800 mg, or placebo, by subcutaneous injection on days 0 and 90. Patients were followed up for at least 270 days. The primary outcome was percent change in apolipoprotein B (apoB) concentration from baseline to day 180 with solbinsiran compared with placebo, analysed under an efficacy estimand (in patients who received at least one dose of the study drug). This trial is completed and registered with ClinicalTrials.gov, NCT05256654. Of 585 patients screened, 205 patients were enrolled in the study between July 20, 2022, and March 4, 2024. Patients (111 [54%] female and 94 [46%] male; median age 57 years [IQR 49-65]) were randomly assigned to receive solbinsiran 100 mg (n=30), solbinsiran 400 mg (n=58), solbinsiran 800 mg (n=59), or placebo (n=58). At baseline, median concentrations were 111 mg/dL (IQR 96-130) for apoB, 2·64 mmol/L (2·06-3·29) for triglycerides, and 3·16 mmol/L (2·57-3·82) for LDL-C. The placebo-adjusted percent change in apoB concentration from baseline at day 180 was -2·8% (95% CI -15·5 to 11·9; p=0·69) for solbinsiran 100 mg; -14·3% (-23·6 to -3·9; p=0·0085) for solbinsiran 400 mg; and -8·3% (-18·3 to 2·9; p=0·14) for solbinsiran 800 mg. Solbinsiran administration was well tolerated, with a low incidence of adverse events. The number of patients with treatment-emergent adverse events was 18 [60%] of 30 patients in the solbinsiran 100 mg group, 30 [52%] of 58 patients in the solbinsiran 400 mg group, 26 [44%] of 59 patients in the solbinsiran 800 mg group, and 37 [65%] of 57 patients in the placebo group. Solbinsiran 400 mg reduced apoB in patients with mixed dyslipidaemia and was generally well tolerated. The impact of solbinsiran on cardiovascular outcomes remains to be investigated. Eli Lilly and Company. Show less

People with mild cognitive impairment (MCI) are candidates for early intervention, but not all progress to Alzheimer's disease (AD) dementia. Identifying a subgroup at highest risk may improve treatment targeting. We analyzed data from participants with MCI enrolled in the Alzheimer's Disease Neuroimaging Initiative (ADNI). Cognitive domains included memory, executive functioning, language, and visuospatial abilities. We evaluated baseline performance and 6-month change scores, using proportional hazards models to estimate associations with time to conversion to AD dementia. The strength of association varied by domain, but in general both baseline performance and 6-month change were associated with conversion. The strongest effects observed for memory and language. Observed associations were largely independent of established risk biomarkers, including APOE genotype, structural MRI measures, and CSF biomarkers. 6-month change scores on cognitive tests may help identify a high-risk subgroup of persons with MCI likely to progress to AD dementia. Systematic review. The authors reviewed the literature using traditional (e.g. PubMed) sources. There is a modest literature on change scores in the context of the AD clinical spectrum, but few investigations have evaluated whether short-term changes may be able to identify a high-risk subgroup of people with MCI. The authors have published a systematic review of this literature (Jutten et al. 2020) and appropriately refer to relevant citations here.Interpretation: Our findings suggest that short-term changes in cognition may be useful as part of a strategy to identify subsets of people with MCI who are at highest risk of conversion. Findings were clearest for memory and language. Domain-specific changes appeared to be independent from other biomarkers used to identify people at highest risk. Domain-specific changes did not appear to be better than changes in global cognition as measured by the MMSE or the CDR-sum of boxes.Future directions: Short-term changes in cognition may be useful to help identify a subgroup of people with MCI at highest risk of conversion to AD dementia. Future work could consider time frames shorter than the 6-month data we had available, better characterizing changes with more than 2 time points, or developing strategies that combine changes in cognition with other biomarkers to identify a subgroup of people with MCI to target for treatment. Show less

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of death. Systemic autoimmune and inflammatory diseases are associated with increased ASCVD risk, severity, and mortality. The inflammatory cytokine interleukin 9 (IL-9) has been linked to murine atherogenesis, raising fundamental questions about the populations in which and the mechanisms by which IL-9 drives ASCVD. Circulating T helper subsets and coronary computed tomography angiography data were analysed in patients with psoriasis. Murine models of psoriatic atherogenesis (imiquimod-ApoE Here, we found that expansion of IL-9-producing T helper cells (Th9) was significantly associated with high-risk radiographic ASCVD in patients with the autoimmune disease psoriasis. Th9 cells were poised to migrate to coronary vessels and were identified in human atherosclerotic plaque from individuals with psoriasis. In vivo, murine inflammatory atherogenesis was prevented by IL-9 blockade and by IL-9 receptor (IL-9R) deletion in endothelial cells. In human arterial endothelial cells, IL-9R/STAT3 signalling promoted endothelial dysfunction via diverse mechanisms including adhesion, activation, angiogenesis, and release of leukocyte chemoattractants. These findings suggest the Th9 Show less