Are insulin sensitizers the new strategy to treat Type 1 diabetes? A long-acting dual amylin and calcitonin receptor agonist improves insulin-mediated glycaemic control and controls body weight.

BACKGROUND AND PURPOSE: Insulin therapies for Type 1 diabetes (T1D) have limitations, such as glucose fluctuations, hypoglycaemia, and weight gain. Only pramlintide is approved with insulin. However, its short half-life limits efficacy, requiring multiple daily injections and increasing hypoglycaemia risk. New strategies are needed to improve glycaemic control. Dual amylin and calcitonin receptor agonists are potent insulin sensitizers developed for Type 2 diabetes (T2D) as they improve glucose control, reduce body weight, and attenuate hyperglucagonemia. However, it is uncertain if they could be used to treat T1D. EXPERIMENTAL APPROACH: Sprague Dawley rats received a single intravenous injection of streptozotocin (STZ) (50 mg·kg-1) to induce T1D. Humulin (1 U/200 g·day-1 or 2 U/200 g·day-1) was continuously infused, while half of the rats received additional KBP-336 (4.5 nmol·kg-1 Q3D) treatment. Bodyweight, food intake, and blood glucose were monitored throughout the study. An oral glucose tolerance test was performed during the study. KEY RESULTS: Treatment with Humulin or Humulin + KBP-336 improved the health of STZ rats. Humulin increased body weight in STZ rats, but KBP-336 attenuated these increases and maintained a significant weight loss. The combination exhibited greater blood glucose reductions than Humulin-treated rats alone, reflected by improved HbA1c levels and glucose control. The combination prevented hyperglucagonemia, reduced amylin levels, and increased pancreatic insulin content, indicating improved insulin sensitivity and beta-cell preservation. CONCLUSION AND IMPLICATIONS: The insulin sensitizer KBP-336 lowered glucagon secretion while attenuating insulin-induced weight gain. Additionally, KBP-336 may prevent hypoglycaemia and improve insulin resistance, which could be a significant advantage for individuals with T1D seeking therapeutic benefits.

OXM-104, a potential candidate for the treatment of obesity, NASH and type 2 diabetes.

OBJECTIVE: Dual glucagon-like peptide-1 (GLP-1) and glucagon receptor agonists are therapeutic agents with an interesting liver-specific mode of action suitable for metabolic complications. In this study, dual GLP-1 and glucagon receptor agonist OXM-104 is compared head-to-head with the once-daily dual GLP-1 and glucagon receptor agonist cotadutide and GLP-1 receptor agonist semaglutide to explore the metabolic efficacy of OXM-104. METHODS: The in vitro potencies of OXM-104, cotadutide and semaglutide were assessed using reporter assays. In addition, in vivo efficacy was investigated using mouse models of diet-induced obesity (DIO mice), diabetes (db/db mice) and diet-induced NASH mice (MS-NASH). RESULTS: OXM-104 was found to only activate the GLP-1 and glucagon with no cross-reactivity at the (GIP) receptor. Cotadutide was also found to activate the GLP-1 and glucagon receptors, whereas semaglutide only showed activity at the GLP-1 receptor. OXM-104, cotadutide, and semaglutide elicited marked reductions in body weight and improved glucose control. In contrast, hepatoprotective effects, i.e., reductions in steatosis and fibrosis, as well as liver fibrotic biomarkers, were more prominent with OXM-104 and cotadutide than those seen with semaglutide, demonstrated by an improved NAFLD activity score (NAS) by OXM-104 and cotadutide, underlining the importance of the glucagon receptor. CONCLUSION: These results show that dual GLP-1 and glucagon receptor agonism is superior to GLP-1 alone. OXM-104 was found to be a promising therapeutic candidate for the treatment of metabolic complications such as obesity, type 2 diabetes and NASH.

Endotrophin, a Key Marker and Driver for Fibroinflammatory Disease.

Our overview covers several key areas related to recent results obtained for collagen type VI and endotrophin (ETP): i) An introduction to the history of ETP, including how it was identified, how it is released and its function and potential receptors. ii) An introduction to the collagen family, with a focus on what differentiates collagen type VI from an evolutionary standpoint. iii) An overview of collagen type VI, the six individual chains (COL6A1, A2, A3, A4, A5 and A6), their differences and similarities, as well as their expression profiles and function. iv) A detailed analysis of COL6A3, including the cleaved product endotrophin, and what separates it from the other five collagen 6 molecules, including its suggested function based on insights gained from knockout and gain of function mouse models. v) An introduction to the history of ETP, including how it was identified, how it is released and its function and potential receptors. vi) The pathology of ETP. What leads to its presence and release and what are the consequences thereof? vii) Functional implications of circulating ETP. Here we review the data with the functional roles of ETP in mind. viii) We propose that ETP is a mediator for fibrotic (or fibro-inflammatory? ) disorders. Based on what we know about ETP, we have to consider it as a target for the treatment of fibrotic (or fibro-inflammatory) disorders. What segment(s) of the patient population would most dramatically respond to an ETP-targeted intervention? How can we find the population that would profit most from an intervention? We aim to present a broad overview over the ETP field at large, providing an assessment of where the future research efforts need to be placed to tap into the vast potential of ETP, both as a marker and as a target in different diseases.

Dual amylin and calcitonin receptor agonist treatment reduces biomarkers associated with kidney fibrosis in diabetic rats.

Dual amylin and calcitonin receptor agonists (DACRAs) are effective treatments for obesity and type 2 diabetes (T2D). They provide beneficial effects on body weight, glucose control, and insulin action. However, whether DACRAs protect against diabetes-related kidney damage remains unknown. We characterize the potential of long-acting DACRAs (KBP-A, Key Bioscience Peptide-A) as a treatment for T2D-related pathological alterations of the kidney extracellular matrix (ECM) in Zucker diabetic fatty rats (ZDF). We examined levels of endotrophin (profibrotic signaling molecule reflecting collagen type VI formation) and tumstatin (matrikine derived from collagen type IVα3) in serum and evaluated kidney morphology and collagen deposition in the kidneys. We included a study in obese Sprague-Dawley rats to further investigate the impact of KBP-A on ECM biomarkers. In ZDF vehicles, levels of endotrophin and tumstatin increased, suggesting disease progression along with an increase in blood glucose levels. These rats also displayed damage to their kidneys, which was evident from the presence of collagen formation in the medullary region of the kidney. Interestingly, KBP-A treatment attenuated these increases, resulting in significantly lower levels of endotrophin and tumstatin than the vehicle. Levels of endotrophin and tumstatin were unchanged in obese Sprague-Dawley rats, supporting the relation to diabetes-related kidney complications. Furthermore, KBP-A treatment normalized collagen deposition in the kidney while improving glucose control. These studies confirm the beneficial effects of DACRAs on biomarkers associated with kidney fibrosis. Moreover, these antifibrotic effects are likely associated with improved glucose control, highlighting KBP-A as a promising treatment of T2D and its related late complications.NEW & NOTEWORTHY These studies describe the beneficial effects of using a dual amylin and calcitonin receptor agonist (DACRA) for diabetes-related kidney complications. DACRA treatment reduced levels of serological biomarkers associated with kidney fibrosis. These reductions were further reflected by reduced collagen expression in diabetic kidneys. In general, these results validate the use of serological biomarkers while demonstrating the potential effect of DACRAs in treating diabetes-related long-term complications.

Dual amylin and calcitonin receptor agonist treatment improves insulin sensitivity and increases muscle-specific glucose uptake independent of weight loss.

Dual amylin and calcitonin receptor agonists (DACRAs) are known to induce significant weight loss as well as improve glucose tolerance, glucose control, and insulin action in rats. However, to what extent DACRAs affect insulin sensitivity beyond that induced by weight loss and if DACRAs affect glucose turnover including tissue-specific glucose uptake is still unknown. Hyperinsulinemic glucose clamp studies were carried out in pre-diabetic ZDSD and diabetic ZDF rats treated with either the DACRA KBP or the long-acting DACRA KBP-A for 12 days. The glucose rate of disappearance was assessed using 3-3H glucose and tissue-specific glucose uptake was evaluated using 14C-2-deoxy-D-glucose (14C-2DG). In diabetic ZDF rats, KBP treatment significantly reduced fasting blood glucose and improved insulin sensitivity independent of weight loss. Furthermore, KBP increased the rate of glucose clearance, likely by increasing glucose storage, but without altering the endogenous glucose production. This was confirmed in pre-diabetic ZDSD rats. Direct assessment of tissue-specific glucose uptake showed, that both KBP and KBP-A significantly increased glucose uptake in muscles. In summary, KBP treatment significantly improved insulin sensitivity in diabetic rats and markedly increased glucose uptake in muscles. Importantly, in addition to their well-established weight loss potential, the KBPs have an insulin-sensitizing effect independent of weight loss, highlighting DACRAs as promising agents for the treatment of type 2 diabetes and obesity.

Treatment sequencing using the dual amylin and calcitonin receptor agonist KBP-336 and semaglutide results in durable weight loss.

OBJECTIVE: Long-acting dual amylin and calcitonin receptor agonists (DACRAs) hold great promise as potential treatments for obesity and its associated comorbidities. These agents have demonstrated beneficial effects on body weight, glucose control, and insulin action mirroring the effects observed with glucagon-like peptide-1 (GLP-1) agonist treatment. Strategies aimed at enhancing and prolonging treatment efficacy include treatment sequencing and combination therapy. Here, we sought to investigate the impact of switching between or combining treatment with the DACRA KBP-336 and the GLP-1 analog semaglutide in fed rats with obesity induced by a high-fat diet (HFD). METHODS: Two studies were performed in which HFD-induced obese Sprague Dawley rats were switched between treatment with KBP-336 (4.5 nmol/kg, Q3D) and semaglutide (50 nmol/kg, Q3D) or a combination of the two. Treatment efficacy on weight loss and food intake was evaluated, and glucose tolerance was assessed by oral glucose tolerance tests. RESULTS: KBP-336 and semaglutide monotherapy resulted in a similar reduction in body weight and food intake. Treatment sequencing resulted in continuous weight loss and all monotherapies resulted in similar weight loss independent of the treatment regimen (P < 0.001 compared to vehicle). The combination of KBP-336 and semaglutide significantly improved the weight loss compared to either monotherapy alone (P < 0.001), which was evident in the adiposity at the study end. All treatments improved glucose tolerance, with the KBP-effect on insulin sensitivity as the dominant response. CONCLUSIONS: These findings highlight KBP-336 as a promising anti-obesity therapy both alone, in treatment sequencing, and in combination with semaglutide or other incretin-based therapies.

Improved metabolic efficacy of a dual amylin and calcitonin receptor agonist when combined with semaglutide or empagliflozin.

Pharmacotherapies for obesity and type 2 diabetes (T2D) are thought to bridge the gap between lifestyle modification and the weight loss obtained with bariatric surgery. Although the effect of monotherapies, namely amylin and glucagon-like peptide-1 receptor (GLP-1R) agonists, has shown great potential, combination therapy is now becoming a strategy to optimize efficacy for weight management while minimizing adverse effects. This study investigated a dual amylin and calcitonin receptor agonist (DACRA); KBP-066A in combination with the GLP-1R agonist semaglutide or the sodium-glucose co transporter-2 inhibitor (SGLT2i) empagliflozin for anti-obesity and anti-diabetic treatment. The effect of KBP-066A, semaglutide, and empagliflozin alone and in combination was studied with respect to their impact on body weight, food intake, and glucose metabolism in high-fat diet (HFD) and Zucker diabetic fatty (fa/fa) (ZDF) rats. Treatment with KBP-066A and semaglutide lowered body weight by 13% and 9.7%. In contrast, a combination of both KBP-066A + semaglutide reduced body weight by 21% in HFD rats demonstrating superiority compared to monotherapies alone. A combination of KBP-066A with semaglutide or empagliflozin significantly lowered fasting blood glucose, and HbA1C (%) levels in ZDF rats. The complementary action by KBP-066A to GLP-1R agonist and SGLT2i on BW, food intake and glucose control endorsed the potential of DACRAs as an add-on therapy to therapeutic options for T2D and obesity.

The Effects of Dual GLP-1/Glucagon Receptor Agonists with Different Receptor Selectivity in Mouse Models of Obesity and Nonalcoholic Steatohepatitis.

There is an unmet need for nonalcoholic steatohepatitis (NASH) therapeutics, considering the increase in global obesity. Dual GLP-1/glucagon (GCG) receptor agonists have shown beneficial effects in circumventing the pathophysiology linked to NASH. However, dual GLP-1/GCG receptor agonists as a treatment of metabolic diseases need delicate optimization to maximize metabolism effects. The impacts of increased relative GLP-1/GCG receptor activity in NASH settings must be addressed to unleash the full potential. In this study, we investigated the potential of OXM-104 and OXM-101, two dual GLP-1/GCG receptor agonists with different receptor selectivity in the setting of NASH, to establish the relative receptor activities leading to the best metabolic outcome efficacies to reduce the gap between surgery and pharmacological interventions. We developed dual GLP-1/GCG receptor agonists with selective agonism. Despite the improved metabolic effects of OXM-101, we explored a hyperglycemic risk attached to increased relative GCG receptor agonism. Thirty-eight days of treatment with a dual GLP-1/GCG receptor agonist, OXM-104, with increased GLP-1 receptor agonism in obese NASH mice was found to ameliorate the development of NASH by lowering body weight, improving liver and lipid profiles, reducing the levels of the fibrosis marker PRO-C4, and improving glucose control. Similarly, dual GLP-1/GCG receptor agonist OXM-101 with increased relative GCG receptor agonism ameliorated NASH by eliciting dramatic body weight reductions to OXM-104, reflected in the improvement of liver and lipid enzymes and reduced PRO-C4 levels. Optimizing dual GLP-1/GCG agonists with increased relative GCG receptor agonism can provide the setting for future agonists to treat obesity, type 2 diabetes, and NASH without having a hyperglycemic risk. SIGNIFICANT STATEMENT: There is an unmet need for nonalcoholic steatohepatitis (NASH) therapeutics, considering the increase in global obesity. Dual GLP-1/glucagon (GCG) receptor agonists have shown beneficial effects in circumventing the pathophysiology linked to NASH. Therefore, this study has examined OXM-104 and OXM-101, two dual GLP-1/GCG receptor agonists in the setting of NASH, to establish the relative receptor activities leading to the best metabolic outcome efficacies to reduce the gap between surgery and pharmacological interventions.

The Impact of Exposure Profile on the Efficacy of Dual Amylin and Calcitonin Receptor Agonist Therapy.

BACKGROUND: Dual Amylin and Calcitonin Receptor Agonists (DACRAs) are treatment candidates for obesity and type 2 diabetes. Recently, a once-weekly DACRA (KBP-A) showed promise, potentially due to its different exposure profile compared to daily DACRA (KBP). Parathyroid hormone, a G-protein-coupled receptor (GPCR) class B agonist, is an example of the exposure profile being critical to the effect. Since KBP and KBP-A also activate GPCR class B, we compared the effects of injection to continuous infusion of short-acting KBP and long-acting KBP-A in obese and diabetic rats to shed light on the role of exposure profiles. METHODS: To explore the metabolic benefits of dose optimization, the following dosing profiles were compared in High Fat Diet (HFD)-fed Sprague-Dawley rats and diabetic Zucker Diabetic Fatty (ZDF) rats: (1) KBP dosed once-daily by injection or by continuous infusion in HFD and ZDF rats; (2) KBP injected once-daily and KBP-A injected once every 3rd day (Q3D) in HFD rats; (3) KBP-A injected Q3D or by infusion in ZDF rats. RESULTS: KBP and KBP-A, delivered by either injection or infusion, resulted in similar weight and food intake reductions in HFD rats. In ZDF rats, injection of KBP improved glucose control significantly compared to infusion, while delivery of KBP-A by injection and continuous infusion was comparable in terms of glucose control. CONCLUSION: different dosing profiles of KBP and KBP-A had no impact on metabolic benefits in HFD rats. In diabetic ZDF rats, KBP by injection instead of infusion was superior, while for KBP-A the effects were similar.

Quantification of Tau-A in serum after brain injury: a comparison of two analytical platforms, ELISA and electrochemiluminescence immunoassay.

BACKGROUND: Previous studies have indicated the utility of the ADAM10-generated fragment of tau, Tau-A, as marker of neuronal damage. However, the sensitivity of the ELISA-based system was limited. OBJECTIVES: We utilized the extensive dynamic range of electrochemiluminescence compared to colorimetric assessment to improve the sensitivity of the Tau-A assay and investigate Tau-A levels after brain injury. METHODS: We converted the Tau-A competitive ELISA to a competitive electrochemiluminescence-based immunoassay, Tau-A ECLIA, and compared the methods by measuring serum samples in a TBI (n = 40) and a stroke cohort (n = 64). RESULTS: The Tau-A ECLIA was technically robust. Only 1% of the samples was below the detection limit in the ECLIA compared to 10.6% in the ELISA . Tau-A measured in both assays could discriminate between patients with a TBI and non-trauma controls (ELISA: p = 0.0005, ECLIA: p = 0.0002). The increased dynamic range of the Tau-A ECLIA also allowed discrimination between healthy controls from patients with hemorrhagic (p = 0.0172) and severe ischemic stroke (p = 0.0118) respectively, as well as patients with mild ischemic stroke from severe (p = 0.0445). CONCLUSIONS: The Tau-A ECLIA was characterized by dynamic range compared to the ELISA, which facilitated a better separation between the patient groups. Tau-A warrants further investigation as a neuronal injury associated marker.

Safety, tolerability and pharmacokinetic characterisation of DACRA KBP-042 in healthy male subjects.

There is a need for antidiabetic agents successfully targeting insulin sensitivity and treating obesity control at the same time. The aim of this first-in-human study was (a) to evaluate safety and tolerability, (b) to evaluate pharmacokinetics and (c) to assess indications of receptor engagement of single ascending doses of KBP-042, a dual amylin and calcitonin receptor agonist (DACRA) that has shown promising preclinical data, with superior activity in terms of typical amylin-induced responses including reduction of food intake, weight loss and gluco-regulatory capacities. A randomised double-blind placebo-controlled single ascending dose study was performed with six dose levels of KBP-042 (5, 7.5, 10, 20, 20 (evening), 40 ug) in healthy male adults. KBP-042 or placebo was administered as a single dose after an overnight fast, followed by a standardized lunch after 4 hours. KBP-042 was associated with dose-dependent complaints of nausea and vomiting, with a lack of tolerability at doses of 20 µg and above. Doses of 5-40 µg KBP-042 behaved according to a linear pharmacokinetic profile. Indications of target receptor engagement were observed at the level of glucose control and lowering of bone resorption, compared to placebo. The results of this study showed that doses up to 40 µg were safe, although tolerability was not present at the highest doses. The study confirmed target receptor engagement at the studied doses.

Gene therapy for infantile malignant osteopetrosis: review of pre-clinical research and proof-of-concept for phenotypic reversal.

Infantile malignant osteopetrosis is a devastating disorder of early childhood that is frequently fatal and for which there are only limited therapeutic options. Gene therapy utilizing autologous hematopoietic stem and progenitor cells represents a potentially advantageous therapeutic alternative for this multisystemic disease. Gene therapy can be performed relatively rapidly following diagnosis, will not result in graft versus host disease, and may also have potential for reduced incidences of other transplant-related complications. In this review, we have summarized the past sixteen years of research aimed at developing a gene therapy for infantile malignant osteopetrosis; these efforts have culminated in the first clinical trial employing lentiviral-mediated delivery of TCIRG1 in autologous hematopoietic stem and progenitor cells.

Treatment with a dual amylin and calcitonin receptor agonist improves metabolic health in an old, obese, and ovariectomized rat model.

OBJECTIVES: Menopause is often characterized by detrimental metabolic changes, such as obesity, insulin resistance, and impaired glucose tolerance, often requiring treatment. KeyBioscience Peptides (KBPs) are Dual Amylin and Calcitonin Receptor Agonists which have shown promising metabolic effects in rats. The objective of this study was to investigate the in vivo effect of KBP on the metabolic health in a model driven by unhealthy diet, age, and menopause. METHODS: Female Sprague Dawley rats were fed a high-fat diet (HFD) for 3 months before the initiation of the study. At 6 months of age the rats were randomized into groups (n = 12) and subjected to ovariectomy surgery and treatment with KBP: (1) Lean-Sham, (2) HFD-Sham, (3) Lean-OVX, (4) HFD-OVX, (5) HFD-OVX-KBP (10 µg/kg/d), (6) HFD-OVX-KBP (20 µg/kg/d), (7) HFD-OVX-EE2 (30 µg/d 17a-ethynylestradiol). Body weight, food intake, oral glucose tolerance tests (OGTTs), subcutaneous fat, visceral fat, liver weight, and uterus weight were assessed during the 6-month study. Statistical analyses were conducted by one-way ANOVA with Tukey post-hoc test for multiple comparisons. RESULTS: Combination of OVX and HFD led to significant induction of obesity (31% weight increase, P < 0.001) and insulin resistance (13% increase in tAUCglucose during OGTT P < 0.01) compared with the relevant control groups (P < 0.05), and this could be completely rescued by EE2 therapy confirming the model system (P < 0.05).Treatment of OVX-HFD rats with KBP for 26 weeks led to a significant reduction in body weight (13%, P < 0.001) in the high dose and 9% (P < 0.01) in the low dose, with corresponding improvements in fat depot sizes, all compared with HFD-OVX controls. As expected, food intake was suppressed, albeit mainly in the first 2 weeks of treatment, resulting in a reduction of overall caloric intake by 6.5% (P < 0.01) and 12.5% (P < 0.001) in the low and high doses respectively. Furthermore, treatment with KBP reduced the weight of visceral and subcutaneous fat tissues. Finally, KBP treatment significantly improved glucose tolerance, assessed using OGTTs at weeks 8, 16, and 24. CONCLUSIONS: The data presented here clearly indicate a positive and sustained effect of KBP treatment on body weight loss, fat depot size, and improved glucose tolerance, illustrating the potential of KBPs as treatments for metabolic complications of overweight and menopause.

The dual amylin and calcitonin receptor agonist KBP-089 and the GLP-1 receptor agonist liraglutide act complimentarily on body weight reduction and metabolic profile.

BACKGROUND: Weight loss therapy is becoming more and more important, and two classes of molecules, namely amylin receptor and GLP-1 receptor agonists, have shown promise in this regard. Interestingly, these molecules have several overlapping pharmacological effects, such as suppression of gastric emptying, reduction of glucagon secretion and weight loss in common; however, they also have distinct effects on prandial insulin secretion. Hence, a combination of these two mechanisms is of significant interest. METHODS: In this study, we investigated the add-on potential of the dual amylin and calcitonin receptor agonist (DACRA) KBP-089 in combination with the GLP-1 receptor agonist liraglutide as obesity treatment in high-fat diet (HFD) fed rats. RESULTS: Increasing doses of KBP-089 and liraglutide alone and in combination were studied with respect to their effects on body weight, food intake and glucose metabolism during a 9-week intervention study conducted in HFD rats. Further, the gastric emptying rate during an oral glucose tolerance was assessed. Treatment with KBP-089 and liraglutide dose-dependently lowered body weight 15% (at 2.5 µg/kg/day) and 7% (at 400 µg/kg/day) in HFD rats, respectively, while the combination resulted in a 21% body weight reduction, which was mirrored by reduction in fat depot sizes. Gastric emptying and glucose metabolism were improved, primarily by KBP-089, although liraglutide led to a reduction in fasting plasma glucagon. CONCLUSION: DACRAs complement GLP-1 on food intake, body weight, and glucose tolerance indicating the potential for an add-on therapy.

Widespread disturbance in extracellular matrix collagen biomarker responses to teriparatide therapy in osteogenesis imperfecta.

Osteogenesis imperfecta (OI), a heritable disorder caused by abnormalities in synthesis or processing of type I collagen, is characterized by skeletal fragility. Type I collagen interacts with multiple components of the extracellular matrix (ECM) including other collagens types. Thus, alterations in structure or quantity may broadly affect ECM homeostasis. In fact, while OI is clinically categorized by severity of bone disease, patients can also present with extra-skeletal manifestations, including the pulmonary, muscle and cardiovascular systems. Parathyroid hormone (PTH) is a regulator of skeletal homeostasis but the receptor for PTH/PTH1R is expressed in a variety of other tissues. Given interactions between type I collagen with other collagens in the ECM and the potential for PTH action on tissues beyond the skeleton, we explored whether serum levels of non-type I collagens are altered in response to teriparatide (human parathyroid hormone 1-34). We measured biomarkers of collagens II, III, IV, V, and VI in serum from individuals with type I and types III/IV OI in response to an 18 month course of teriparatide or placebo. These results were compared to similar biomarker measures in postmenopausal (PM) women without OI treated with teriparatide. In type I OI, teriparatide therapy increased concentrations of biomarkers of collagens II, III, IV, V, and VI. In individuals with types III/IV OI these biomarker changes in response to teriparatide were blunted, as we previously reported with collagen I biomarkers during teriparatide therapy. In contrast to OI, in PM women there were no effects of teriparatide on the collagen biomarkers we assessed (II, V, and VI). These findings suggest that in OI teriparatide therapy has abnormal effects on the homeostasis of many ECM collagens likely derived from skeletal as well as extra-skeletal tissues.

Mono and dual agonists of the amylin, calcitonin, and CGRP receptors and their potential in metabolic diseases.

BACKGROUND: Therapies for metabolic diseases are numerous, yet improving insulin sensitivity beyond that induced by weight loss remains challenging. Therefore, search continues for novel treatment candidates that can stimulate insulin sensitivity and increase weight loss efficacy in combination with current treatment options. Calcitonin gene-related peptide (CGRP) and amylin belong to the same peptide family and have been explored as treatments for metabolic diseases. However, their full potential remains controversial. SCOPE OF REVIEW: In this article, we introduce this rather complex peptide family and its corresponding receptors. We discuss the physiology of the peptides with a focus on metabolism and insulin sensitivity. We also thoroughly review the pharmacological potential of amylin, calcitonin, CGRP, and peptide derivatives as treatments for metabolic diseases, emphasizing their ability to increase insulin sensitivity based on preclinical and clinical studies. MAJOR CONCLUSIONS: Amylin receptor agonists and dual amylin and calcitonin receptor agonists are relevant treatment candidates, especially because they increase insulin sensitivity while also assisting weight loss, and their unique mode of action complements incretin-based therapies. However, CGRP and its derivatives seem to have only modest if any metabolic effects and are no longer of interest as therapies for metabolic diseases.

Bone phenotypes in rheumatology - there is more to bone than just bone.

Osteoarthritis, rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis, all have one clear common denominator; an altered turnover of bone. However, this may be more complex than a simple change in bone matrix and mineral turnover. While these diseases share a common tissue axis, their manifestations in the area of pathology are highly diverse, ranging from sclerosis to erosion of bone in different regions. The management of these diseases will benefit from a deeper understanding of the local versus systemic effects, the relation to the equilibrium of the bone balance (i.e., bone formation versus bone resorption), and the physiological and pathophysiological phenotypes of the cells involved (e.g., osteoblasts, osteoclasts, osteocytes and chondrocytes). For example, the process of endochondral bone formation in chondrocytes occurs exists during skeletal development and healthy conditions, but also in pathological conditions. This review focuses on the complex molecular and cellular taxonomy of bone in the context of rheumatological diseases that alter bone matrix composition and maintenance, giving rise to different bone turnover phenotypes, and how biomarkers (biochemical markers) can be applied to potentially describe specific bone phenotypic tissue profiles.

Matrix metalloproteinase-degraded type I collagen is associated with APOE/TOMM40 variants and preclinical dementia.

OBJECTIVE: Dysregulation of type I collagen metabolism has a great impact on human health. We have previously seen that matrix metalloproteinase-degraded type I collagen (C1M) is associated with early death and age-related pathologies. To dissect the biological impact of type I collagen dysregulation, we have performed a genome-wide screening of the genetic factors related to type I collagen turnover. METHODS: Patient registry data and genotypes have been collected for a total of 4,981 Danish postmenopausal women. Genome-wide association with serum levels of C1M was assessed and phenotype-genotype association analysis performed. RESULTS: Twenty-two genome-wide significant variants associated with C1M were identified in the APOE-C1/TOMM40 gene cluster. The APOE-C1/TOMM40 gene cluster is associated with hyperlipidemia and cognitive disorders, and we further found that C1M levels correlated with tau degradation markers and were decreased in women with preclinical cognitive impairment. CONCLUSIONS: Our study provides elements for better understanding the role of the collagen metabolism in the onset of cognitive impairment.

Transcriptome sequencing identifies a noncoding, deep intronic variant in CLCN7 causing autosomal recessive osteopetrosis.

BACKGROUND: Over half of children with rare genetic diseases remain undiagnosed despite maximal clinical evaluation and DNA-based genetic testing. As part of an Undiagnosed Diseases Program applying transcriptome (RNA) sequencing to identify the causes of these unsolved cases, we studied a child with severe infantile osteopetrosis leading to cranial nerve palsies, bone deformities, and bone marrow failure, for whom whole-genome sequencing was nondiagnostic. METHODS: We performed transcriptome (RNA) sequencing of whole blood followed by analysis of aberrant transcript isoforms and osteoclast functional studies. RESULTS: We identified a pathogenic deep intronic variant in CLCN7 creating an unexpected, frameshifting pseudoexon causing complete loss of function. Functional studies, including osteoclastogenesis and bone resorption assays, confirmed normal osteoclast differentiation but loss of osteoclast function. CONCLUSION: This is the first report of a pathogenic deep intronic variant in CLCN7, and our approach provides a model for systematic identification of noncoding variants causing osteopetrosis-a disease for which molecular-genetic diagnosis can be pivotal for potentially curative hematopoietic stem cell transplantation. Our work illustrates that cryptic splice variants may elude DNA-only sequencing and supports broad first-line use of transcriptome sequencing for children with undiagnosed diseases.

The CNS-specific proteoglycan, brevican, and its ADAMTS4-cleaved fragment show differential serological levels in Alzheimer's disease, other types of dementia and non-demented controls: A cross-sectional study.

Evidence indicate that the brain-specific protein, brevican, is proteolytically cleaved during neurodegeneration, hence positioning fragments of brevican as potential blood biomarkers of neurodegenerative diseases, such as dementia. We aimed to develop two assays capable of detecting the brevican N-terminal (N-Brev) and the ADAMTS4-generated fragment (Brev-A), cleaved at Ser401, in serum and to perform a preliminary assessment of their diagnostic potential in dementias. Monoclonal antibodies against N-Brev and Brev-A were used to develop two ELISAs detecting each epitope. A comparison of brevican fragments in serum from individuals with AD (n = 28), other dementia (OD) (n = 41), and non-dementia-related memory complaints (NDCs) (n = 48) was conducted. Anti-N-Brev and anti-Brev-A antibodies selectively recognized their targets and dilution and spike recoveries were within limits of ±20%. Intra- and inter-assay CVs were below limits of 10% and 15%, respectively. For the N-Brev biomarker, serum from patients with OD showed significantly lower levels than those with AD (p = 0.05) and NDCs (p < 0.01). The opposite pattern was evident for Brev-A: serum levels in patients with OD were significantly higher than for AD (p = 0.04) and NDCs (p = 0.01). For both N-Brev and Brev-A, levels did not differ between AD and NDCs. The ratio of N-Brev/Brev-A resulted in increased significant differences between OD and AD (p < 0.01) and between OD and NDCs (p < 0.0001). The ratio discriminated between NDCs and OD (AUC: 0.75, 95% CI: 0.65-0.85, p < 0.0001) and between OD and AD (AUC: 0.72, 95% CI: 0.59-0.85, p < 0.01). In conclusion, we developed the first assays detecting the N-terminal of brevican as well as an ADAMTS4-cleaved fragment of brevican in blood. Differential levels of N-Brev and Brev-A between AD and OD allow for these biomarkers to possibly distinguish between different forms of dementias.