Asprosin response in hypoglycemia is not related to hypoglycemia unawareness but rather to insulin resistance in type 1 diabetes

Asprosin aggravates nonalcoholic fatty liver disease via inflammation and lipid metabolic disturbance mediated by reactive oxygen species

Asprosin (ASP) is a newly-identified adipokine and plays important roles in energy metabolism homeostasis. However, there is no report on whether and how ASP is involved in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Therefore, in the study, we investigated the protective effects of ASP-deficiency on the liver in the NAFLD model mice and the detrimental effects of ASP treatment on the human normal hepatocytes (LO2 cell line). More important, we explored the underlying mechanism from the perspective of lipid metabolism and inflammation. In the in vivo experiments, our data showed that the ASP-deficiency significantly alleviated the high-fat diet-induced inflammation and NAFLD, inhibited the hepatic fat deposition and downregulated the expressions of fat acid synthase (FASN), peroxisome proliferator-activated receptor γ (PPARγ) and forkhead box protein O1 (FOXO1); moreover, the ASP-deficiency attenuated the inflammatory state and inhibited the activation of the IKK/NF-κBp65 inflammation pathway. In the in vitro experiments, our results revealed that ASP treatment caused and even exacerbated the injury of LO2 cells induced by FFA; In contrast, the ASP treatment upregulated the expressions of PPARγ, FOXO1, FASN, ACC and acyl-CoA oxidase 1 (ACOX1) and elevated the reactive oxygen species (ROS) levels. Accordingly, these results demonstrate that ASP causes NAFLD through disrupting lipid metabolism and promoting the inflammation mediated by ROS.

Circulating levels of asprosin in children with obesity: a systematic review and meta-analysis

BACKGROUND

Prior studies reported that elevated asprosin level was associated with obesity in adults and animal models. However, the relationship between asprosin level and children with obeisty remains controversial. The aim of our analysis was to systematically review available literatures linking asprosin and children with obesity for a comprehensive understanding of the relationship between circulating asprosin level and obesity in children.

METHODS

Eight databases were gleaned for studies published up to January 2024. Standard mean difference with 95% confidence interval (CI) and Fisher's Z transformation was calculated to evaluate the relationship between asprosin level and children with obesity using the Review Manager 5.4 Software. Other indicators were measured via mean difference with 95% CI.

RESULTS

Six observational studies were included both in systematic review and meta-analysis. The current evidence indicated that no significant difference was observed in the level of circulating asprosin between the children with and without obesity (SMD = 0.37; 95% CI:-0.22-0.95, p = 0.22). However, Fisher's Z transformation suggested the positive association of circulating asprosin levels and clinical index measuring the degree of obesity: total cholesterol (Fisher's Z: 0.11, 95% CI: 0.02-0.20, p = 0.02).

CONCLUSIONS

Circulating asprosin level was not independently related to childhood obesity currently. More rigorous longitudinal researches were required to disentangle the causations. However, the positive association of asprosin levels and total cholesterol indicated that asprosin might get involved in the lipid-metabolism of childhood obesity, asprosin might be a prospective bio-index and targeted treatment of total cholesterol metabolism besides the role of glucogenic and orexigenic.

TRIAL REGISTRATION

Prospero ID: CRD42023426476.

Increased RBP4 and Asprosin Are Novel Contributors in Inflammation Process of Periodontitis in Obese Rats

There is a significant comorbidity between obesity and periodontitis, while adipokines are pivotal in the immunoinflammatory process, which may play a role in this special relationship. We aimed to assess the effect of adipokines as mediators in the progression of periodontitis in obese Sprague Dawley rats. Rats were divided into four groups: normal body weight with and without periodontitis and obesity with and without periodontitis. Experimental obesity and periodontitis were induced by a high-fat diet or ligaturing, and the effect was measured using metabolic and micro-computed tomography analysis and histological staining. Compared with the other three groups, the group of periodontitis with obesity (OP) had the heaviest alveolar bone absorption, the largest increase in osteoclasts, the utmost inflammatory cell infiltration and the highest expressions of pro-inflammatory cytokines and nuclear factor-kappa B ligand (RANKL); meanwhile, its expression of the osteogenesis-related gene was the lowest among the four groups. The expressions of leptin, visfatin, resistin, retinol-binding protein 4 (RBP4) and asprosin were upregulated, while adiponectin was decreased significantly in OP. The strong positive associations between the periodontal or circulating levels of RBP4 (or asprosin) and the degree of alveolar resorption in experimental periodontitis and obese rats were revealed. The upregulated expression of inflammation biomarkers, the corresponding degradation in connective tissue and the generation of osteoclasts in periodontitis were activated and exacerbated in obesity. The elevated level of RBP4/asprosin may contribute to a more severe periodontal inflammatory state in obese rats.

Asprosin, a novel glucogenic adipokine: a potential therapeutic implication in diabetes mellitus

OBJECTIVES

We aimed to investigate the effects of asprosin on diabetes with a focus on serum glucose, irisin, ghrelin, leptin levels and hepatic levels of triglycerides (TG), cholesterol, low-density lipoprotein (LDL).

METHODS

Asprosin (10 µg/kg) was administered intraperitoneally four times at 3-day intervals and then blood and hepatic parameters above mentioned were investigated in control and diabetic mice.

RESULTS

The administration of asprosin increased blood glucose level in healthy animals (p = .05) whereas it did not change blood glucose level in diabetic animals. In addition, while asprosin decreased irisin level and increased ghrelin level, it did not change leptin level in diabetic mice. Therewithal, asprosin decreased the increasing levels in hepatic TG, cholesterol, and LDL in diabetic mice.

CONCLUSIONS

Our novel findings implicate that asprosin may be a target molecule in preventing the development and complications of diabetes.

Can the new adipokine asprosin be a metabolic troublemaker for cardiovascular diseases? A state-of-the-art review

Adipokines play a significant role in cardiometabolic diseases. Asprosin, a newly discovered adipokine, was first identified as a glucose-raising protein hormone. Asprosin also stimulates appetite and regulates glucose and lipid metabolism. Its identified receptors so far include Olfr734 and Ptprd. Clinical studies have found that asprosin may be associated with cardiometabolic diseases. Asprosin may have diagnostic and therapeutic potential in obesity, diabetes, metabolic syndrome and atherosclerotic cardiovascular diseases. Herein, the structure, receptors, and functions of asprosin and its relationship with cardiometabolic diseases are summarized based on recent findings.

Betatrophin, elabela, asprosin, glucagon and subfatin peptides in breast tissue, blood and milk in gestational diabetes

We investigated the presence of asprosin (ASP), betatrophin, elabela (ELA), glucagon and subfatin (SUB) in the milk of mothers with gestational diabetes mellitus (GDM) and compared their levels with blood levels. We also investigated whether these peptides are synthesized by the breast. We investigated 12 volunteer mothers with GDM and 14 pregnant non-GDM control mothers. The peptides were measured using ELISA and their tissue localization was determined using immunohistochemistry. Breast milk contains ASP, betatrophin, ELA, glucagon and SUB. The amount of the peptides ranged from highest to the lowest in colostrum, transitional milk and mature milk. The amount of peptides in the milk was greater than for blood. The peptides, except for ELA, were increased in milk and blood by GDM. Betatrophin and ELA are synthesized in the connective tissue of the breast. ASP, glucagon and SUB are synthesized in the alveolar tissue of the breast. These peptides in breast milk may contribute to the development of the gastrointestinal tract of newborns and infants.

Asprosin Enhances Cytokine Production by a Co-Culture of Fully Differentiated Mature Adipocytes and Macrophages Leading to the Exacerbation of the Condition Typical of Obesity-Related Inflammation

Asprosin, a fasting-induced, glucogenic, and orexigenic adipokine, has gained popularity in recent years as a potential target in the fight against obesity and its complications. However, the contribution of asprosin to the development of moderate obesity-related inflammation remains still unknown. The present study aimed to evaluate the effect of asprosin on the inflammatory activation of adipocyte–macrophage co-cultures at various stages of differentiation. The study was performed on co-cultures of the murine 3T3L1 adipocyte and the RAW264.7 macrophage cell lines treated with asprosin before, during, and after 3T3L1 cell differentiation, with or without lipopolysaccharide (LPS) stimulation. Cell viability, overall cell activity, and the expression and release of key inflammatory cytokines were analyzed. In the concentration range of 50–100 nM, asprosin increased the pro-inflammatory activity in the mature co-culture and enhanced the expression and release of tumor necrosis factor α (TNF-α), high-mobility group box protein 1 (HMGB1), and interleukin 6 (IL-6). Macrophage migration was also increased, which could be related to the upregulated expression and release of monocyte chemoattractant protein-1 (MCP-1) by the adipocytes. In summary, asprosin exerted a pro-inflammatory effect on the mature adipocyte–macrophage co-culture and may contribute to the spread of moderate obesity-associated inflammation. Nevertheless, further research is needed to fully elucidate this process.

Elevated markers of DNA damage and senescence are associated with the progression of albuminuria and restrictive lung disease in patients with type 2 diabetes

BACKGROUND

This study was conducted to investigate the cascade involving DNA damage, senescence, and senescence-associated secretory phenotype (SASP) in experimental diabetes and in a four-year follow-up study in patients with pre-diabetes and type 2 diabetes.

METHODS

Kidney, lung, and liver were studied in 4 months diabetic db/db mice and age-matched controls for the presence of DNA damage and fibrosis. DNA damage (comet-tail-length and ɤH2Ax-positivity in white blood cells), urinary p21-excretion, and plasma IL-6 and TGF-β1 were determined from 115 healthy participants, 34 patients with pre-diabetes and 221 with type 2 diabetes. Urinary albumin-creatinine-ratio, lung function, and transient elastography of the liver were performed in a prospective follow-up study over 4 years.

FINDINGS

db/db mice showed an increased nuclear ɤH2AX signal in all tissues as compared to the background control. Markers for DNA damage, senescence, and SASP were increased in patients with diabetes. The presence of nephropathy, restrictive lung disease (RLD), and increased liver stiffness was in a cross-sectional design associated with increased markers for DNA damage, senescence, and SASP. The progression of nephropathy over 4 years was predicted by increased DNA damage, senescence, and SASP, while the progression of RLD was associated with increased DNA damage and IL-6 only. The progression of liver stiffness was not associated with any of these parameters. HbA1c was not predictive for progression.

INTERPRETATION

In db/db mice, the cascade of DNA damage is associated with diabetes-related complications. In patients with diabetes, the progression of complications in the kidney and lung is predicted by markers reflecting DNA damage, and senescence-triggered organ fibrosis.

FUNDING

This work was supported by the German Research Foundation (DFG) in the CRC 1118 and CRC 1158, by the GRK DIAMICOM, by the German Center for Diabetes Research (DZD e.V.), and by the Ministry of Science, Research and the Arts, Baden-Württemberg (Kompetenznetzwerk Präventivmedizin).

Asprosin promotes feeding through SK channel-dependent activation of AgRP neurons

Asprosin, a recently identified adipokine, activates agouti-related peptide (AgRP) neurons in the arcuate nucleus of the hypothalamus (ARH) via binding to protein tyrosine phosphatase receptor δ (Ptprd) to increase food intake. However, the intracellular mechanisms responsible for asprosin/Ptprd-mediated activation of AgRPARH neurons remain unknown. Here, we demonstrate that the small-conductance calcium-activated potassium (SK) channel is required for the stimulatory effects of asprosin/Ptprd on AgRPARH neurons. Specifically, we found that deficiency or elevation of circulating asprosin increased or decreased the SK current in AgRPARH neurons, respectively. AgRPARH-specific deletion of SK3 (an SK channel subtype highly expressed in AgRPARH neurons) blocked asprosin-induced AgRPARH activation and overeating. Furthermore, pharmacological blockade, genetic knockdown, or knockout of Ptprd abolished asprosin's effects on the SK current and AgRPARH neuronal activity. Therefore, our results demonstrated an essential asprosin-Ptprd-SK3 mechanism in asprosin-induced AgRPARH activation and hyperphagia, which is a potential therapeutic target for the treatment of obesity.

Association of cord blood asprosin concentration with atherogenic lipid profile and anthropometric indices

BACKGROUND

Elevated lipids in umbilical cord blood affect fetal programming, leading to a higher risk of developing cardiovascular disease in later life. However, the causes of changes in the lipid profile of umbilical cord blood are not clear yet. This study aimed for the first time to determine the association of asprosin concentration with TAG, TC, HDL-C, LDL-C concentrations and TAG/HDL-C, TC/HDL-C, LDL-C/HDL-C and non-HDL-C/HDL-C ratio in umbilical cord blood as well as newborn anthropometric indices. This cross-sectional study was based on 450 mother- newborn pairs of a birth cohort study in Sabzevar, Iran. Multiple linear regression was used to estimate the association of lipid concentration and lipid ratios as well as birth weight (BW), birth length (BL), head circumference (HC) and chest circumference (CC) with asprosin in cord blood samples controlled for the relevant covariates.

RESULT

In fully adjusted models, each 1 ng/mL increase in asprosin was associated with 0.19 (95% CI 0.06, 0.31, P < 0.01), 0.19 (95% CI 0.10, 0.29, P < 0.01), 0.17 (95% CI 0.09, 0.25, P < 0.01), 0.17 (95% CI 0.09, 0.25, P < 0.01), 0.01 (95% CI 0.00, 0.013, P < 0.01), 0.01 (95% CI 0.01, 0.01, P < 0.01), 0.01 (95% CI 0.01, 0.01, P < 0.01) and 0.01 (95% CI 0.01, 0.01, P < 0.01) increase in TAG, TC, LDL-C, TAG/HDL-C, TC/HDL-C, LDL-C/HDL-C and non-HDL-C/HDL-C ratio respectively. Moreover, higher asprosin levels was positively associated with newborn BW, BL, HC and CC; however, these associations were not statistically significant.

CONCLUSION

Overall, our findings support the positive association between cord asprosin concentration and the development of atherogenic lipid profile in newborns. Further studies are needed to confirm the findings of this study in other populations.

Asprosin, a C-Terminal Cleavage Product of Fibrillin 1 Encoded by the FBN1 Gene, in Health and Disease

BACKGROUND

Asprosin is a novel fasting-induced, glucogenic, and orexigenic protein hormone that is discovered with the help of genetic studies in patients with neonatal progeroid syndrome. Asprosin is encoded by the penultimate 2 exons (65 and 66) of the fibrillin 1 (FBN1) gene. Profibrillin 1 is the unprocessed protein product of FBN1 and undergoes a proteolytic cleavage by furin enzyme to produce mature fibrillin 1 and asprosin. The main organ responsible for the asprosin production seems to be white adipose tissue.

SUMMARY

Asprosin promotes hepatic glucose release in the liver and appetite stimulation in the hypothalamus through activation of the cAMP signaling circuitry through interacting with its G protein-coupled receptor, called OR4M1. Increasing mass of evidence suggests that asprosin is involved in the development and progression of various clinical conditions including diabetes, obesity, cardiomyopathy, cancer, and polycystic ovarian syndrome. It regulates various cellular and physiological processes such as appetite stimulation, glucose release, insulin secretion, apoptotic cell death, and inflammatory response. In this review, we discuss the current literature on asprosin and try to shed light on the yet undiscovered functions of asprosin.

KEY MESSAGE

Asprosin is a key regulatory factor for preserving the homeostasis of energy metabolism.

Asprosin, a novel therapeutic candidate for painful neuropathy: an experimental study in mice

Recent studies indicate presence of a strong link between adipokines and neuropathic pain. However, the effects of asprosin, a novel adipokine, on neuropathic pain have not been studied in animal models.Mouse models were employed to investigate the antinociceptive effectiveness of asprosin in the treatment of three types of neuropathic pain, with metabolic (streptozocin/STZ), toxic (oxaliplatin/OXA), and traumatic (sciatic nerve ligation/CCI [chronic constriction nerve injury]) etiologies, respectively. Changes in nociceptive behaviors were assessed relative to controls using thermal (the hot plate and cold plate tests, at 50 °C and 4 °C respectively) and mechanical pain (von Frey test) tests after intraperitoneal (i.p.) administration of asprosin (10 µg/kg) and gabapentin (50 mg/kg) in several times intervals. Besides, possible effect of asprosin on the motor coordination of mice was assessed with a rotarod test. Serum level of asprosin was quantified by ELISA.In neuropathic pain models (STZ, OXA, and CCI), asprosin administration significantly reduced both mechanical and thermal hypersensitivity, indicating that it exhibits a clear-cut antihypersensitivity effect in the analyzed neuropathic pain models. The most effective time of asprosin on pain threshold was observed 60 min after its injection. Also, asprosin displayed no notable effect on the motor activity. Asprosin levels were significantly lower in neuropathic pain compared to healthy group (p < 0.05).The results yielded by the present study suggest that asprosin exhibits an analgesic effect in the neuropathic pain models and may have clinical utility in alleviating chronic pain associated with disease and injury originating from peripheral structures.

Sensitive asprosin detection in clinical samples reveals serum/saliva correlation and indicates cartilage as source for serum asprosin

The C-terminal pro-fibrillin-1 propeptide asprosin is described as white adipose tissue derived hormone that stimulates rapid hepatic glucose release and activates hunger-promoting hypothalamic neurons. Numerous studies proposed correlations of asprosin levels with clinical parameters. However, the enormous variability of reported serum and plasma asprosin levels illustrates the need for sensitive and reliable detection methods in clinical samples. Here we report on newly developed biochemical methods for asprosin concentration and detection in several body fluids including serum, plasma, saliva, breast milk, and urine. Since we found that glycosylation impacts human asprosin detection we analyzed its glycosylation profile. Employing a new sandwich ELISA revealed that serum and saliva asprosin correlate strongly, depend on biological sex, and feeding status. To investigate the contribution of connective tissue-derived asprosin to serum levels we screened two cohorts with described cartilage turnover. Serum asprosin correlated with COMP, a marker for cartilage degradation upon running exercise and after total hip replacement surgery. This together with our finding that asprosin is produced by primary human chondrocytes and expressed in human cartilage suggests a contribution of cartilage to serum asprosin. Furthermore, we determined asprosin levels in breast milk, and urine, for the first time, and propose saliva asprosin as an accessible clinical marker for future studies.

Serum levels of Asprosin in patients diagnosed with coronary artery disease (CAD): a case-control study

Background

Coronary artery disease (CAD) is considered as a multi-faceted chronic inflammatory disease involving reduced blood supply to the myocardium as a result of accumulating lipids in the atrial walls. Visceral adiposity with disrupted release of adipokines play a key role in its pathogenesis. Asprosin is a newly identified fasting-induced glucogenic adipokine that has been related with metabolic disorders such as type II diabetes mellitus and polycystic ovary syndrome. The preset study sought to assess circulating asprosin in context of CAD.

Methods

In this study, serum levels of asprosin were determined in 88 CAD patients and 88 non-CAD healthy controls. Serum IL-6, TNF-α, asprosin and adiponectin were assessed using ELISA kits.

Results: Serum asprosin was found to be higher in CAD patients when compared to non-CAD subjects (7.84 ± 2.08 versus 5.02 ± 1.29 μg/mL, p <  0.001). Similarly, serum TNF-α, and IL-6 elevated in CAD group significantly (p <  0.001). However, circulating adiponectin diminished in CAD group when compared with non-CAD subjects (p < 0.001). Moreover, serum asprosin levels directly correlated with BMI, FBG, HOMA-IR, TG and TC. Logistic regression analyses showed that asprosin levels were associated with increased risk of developing CAD (odds ratio: 3.01, 95% CI: 2.16, 4.20 and p < 0.001), after adjusting for potential confounders (age, sex and BMI).

Conclusions

The present study findings suggested a possible relation of serum asprosin with the pathogenesis of CAD, in particular through insulin resistance and dyslipidemia.

An investigation of the relationship between new fasting hormone asprosin, obesity and acute-chronic exercise: current systematic review

The purpose of this study was to reveal the relationship between new fasting hormone asprosin, obesity, and acute-chronic exercise. The prisma guidelines were followed in forming the methodological model of this review. The articles between 2016 and 2020 (including March) were identified by scanning Google Scholar, Pub Med, and Science Direct databases. Thirty-five articles were defined from 188 articles. Three cross-sectional, and 1 prospective cohort design studies in adults, and 3 cross-sectional studies in children were found. Three randomised-control group designed studies which examined the effect of acute exercise on serum asprosin levels in obese individuals. Asprosin may be a new therapeutic biomarker to be considered in the development, but long-term and deep-rooted researches are needed, and increasing the number of studies examining the effect of exercise on asprosin in the future might help us to identify the mechanisms underlying the decrease or increase in asprosin after exercise.

Asprosin-A Fasting-Induced, Glucogenic, and Orexigenic Adipokine as a New Promising Player. Will It Be a New Factor in the Treatment of Obesity, Diabetes, or Infertility? A Review of the Literature

Asprosin is a recently discovered protein released during fasting conditions mainly by adipocytes from white adipose tissue. As a glucogenic peptide, it stimulates the release of glucose from hepatic cells by binding to the OLFR734 receptor and leading to the activation of the G protein-cAMP-PKA pathway. As it crosses the blood–brain barrier, it also acts as an orexigenic peptide that stimulates food intake through activation of AgRP neurons in the hypothalamus; thus, asprosin participates in maintaining the body’s energy homeostasis. Moreover, studies have shown that asprosin levels are pathologically elevated in obesity and related diseases. However, the administration of anti-asprosin antibodies can both normalize its concentration and reduce food intake in obese mice, which makes it an interesting factor to combat obesity and related diseases. Current research also draws attention to the relationship between asprosin and fertility, especially in men. Asprosin improves age- and obesity-related decrease in fertility potential by improving sperm motility. It should also be mentioned that plasma asprosin levels can be differentially modulated by physical activity; intense anaerobic exercise increases asprosin level, while aerobic exercise decreases it. However, further research is necessary to confirm the exact mechanisms of asprosin activity and its potential as a therapeutic target.

[Effect of high-fat diet and exercise on asprosin and CTRP6 expression in subcutaneous and retroperitoneal adipose tissues in rats during mid-gestation]

OBJECTIVE

To study the effects of high-fat (HF) diet and exercise on the expressions of asprosin and CTRP6 in adipose tissues in different regions of rats during mid-gestation.

METHODS

Pregnant SD rats were fed on a standard chow diet or a high-fat (60% fat content) diet for 14 days starting on gestation day (GD) 1. Starting from GD3, the rats fed either on normal or high-fat diet in the exercise groups (CH-RW and HF-RW groups) were allowed access to the running wheels for voluntary running, and those in sedentary groups (CH-SD and HF-SD groups) remained sedentary. At the end of the 14 days, adipose tissues were sampled from different regions of the rats for detecting the mRNA and protein expressions of asprosin and CTRP6 using RT-qPCR and Western blotting.

RESULTS

The mRNA expression of asprosin in retroperitoneal adipose tissues was significantly higher in HF-RW group than in the other 3 groups (P < 0.0001). Asprosin mRNA expression in subcutaneous adipose tissues was significantly higher in HF-SD group than in CH-SD group (P=0.0234) and comparable between HF-RW and CH-SD groups (P=0.0494). CTRP6 mRNA expression in retroperitoneal adipose tissues was also significantly higher in HF-RW group than in the other groups (P < 0.0001), and CTRP6 protein expression was signficiantly higher in HF-RW group than in CH-RW and HF-SD groups (P < 0.05). In subcutaneous adipose tissues, CTRP6 mRNA expression was significantly higher in CH-RW group than in HF-SD and HF-RW groups (P < 0.05). The protein expression level of CTRP6 in subcutaneous adipose tissues showed a significant negative correlation with blood glucose (r=-0.6038, P=0.0172), while its expression in retroperitoneal adipose tissues was positively correlated with blood glucose (r=0.5305, P= 0.0285); the mRNA expression levels of asprosin and CTRP6 were significantly lower in subcutaneous than in retroperitoneal adipose tissues (P < 0.0001).

CONCLUSIONS

High-fat diet and exercise during mid-gedtation can affect the expression levels of asprosin and CTRP6 in adipose tissues of rats in a site-specific manner.

Novel Targets in Glucose Homeostasis and Obesity-Lesson from Rare Mutations

PURPOSE OF REVIEW

Obesity and diabetes have already become the second largest risk factor for cardiovascular disease. During the last decade, remarkable advances have been made in understanding the human genome's contribution to glucose homeostasis disorders and obesity. A few studies on rare mutations of candidate genes provide potential genetic targets for the treatment of diabetes and obesity. In this review, we discussed the detailed findings of these studies and the possible causalities between specific genetic variations and dysfunctions in energy or glucose homeostasis. We are optimistic that novel therapeutic strategies targeting these specific mutants for treating and preventing diabetes and obesity will be developed in the near future.

RECENT FINDINGS

Studies on rare genetic mutation-caused obesity or diabetes have identified potential genetic targets to decrease body weight or reduce the risk of diabetes. Rare mutations observed in lipodystrophy, obese, or diabetic human patients are promising targets in the treatment of diabetes and obesity.

Higher Serum Asprosin Level is Associated with Urinary Albumin Excretion and Renal Function in Type 2 Diabetes

AIM

We detected whether serum asprosin levels play a role in the occurrence and development of albuminuria in patients with type 2 diabetes mellitus (T2DM), which has not been previously discussed.

METHODS

Based on urinary albumin/creatinine ratio (UACR), 207 T2DM patients were divided into T2DM patients with normoalbuminuria (UACR<30 mg/g), microalbuminuria (30≤UACR<300 mg/g), and macroalbuminuria (UACR≥300 mg/g). Serum asprosin levels were determined by enzyme-linked immunosorbent assay.

RESULTS

Comparatively, the serum asprosin levels in T2DM patient groups with macroalbuminuria [2.37 (1.63-3.57)] and microalbuminuria [2.10 (1.60-2.90)] were significantly increased than the normoalbuminuria group [1.59 (1.18-2.09)] (P<0.001). Importantly, the serum level of asprosin was positively correlated with UACR (r=0.304, P<0.001), creatinine (r=0.157, P=0.024), blood urea nitrogen (BUN) (r=0.244, P<0.001), and negatively with glomerular filtration rate (eGFR) (r=-0.159, P=0.022). Furthermore, multiple stepwise regression analyses showed that asprosin was significantly and independently related to UACR, BUN, DBP, and LDL-C (P<0.05). Besides, after adjustment for the confounders, the serum asprosin level was constantly and independently associated with the development of albuminuria in T2DM patients [OR (95% CI): 2.003 (1.37~2.928), P <0.001].

CONCLUSION

Obviously, the serum asprosin level was independently correlated with UACR in T2DM patients, which implies circulating asprosin may play an essential role in the pathogenesis of diabetic nephropathy.

Serum concentration of asprosin in new-onset type 2 diabetes

BACKGROUND

Asprosin, a newly identified adipokine, is pathologically increased in individuals with insulin resistance. However, the available evidence on the association of asprosin and type 2 diabetes mellitus (T2DM) status is still scarce. Therefore, this study aimed to determine the relationship between serum concentrations of asprosin and T2DM status.

METHODS

This observational study was performed based on 194 adults (97 newly diagnosed T2DM and 97 healthy individuals). Anthropometric and biochemical variables were determined in all participants. Serum concentrations of asprosin were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

In patients with T2DM, the serum concentrations of asprosin were significantly higher than the healthy controls (4.18 [IQR: 4.4] vs. 3.5 [IQR: 1.85], P < 0.001). The concentrations of asprosin were significantly correlated with body mass index (BMI) and fasting blood glucose (FBG) in healthy subjects and with BMI, FBG, hemoglobin A1c (HbA1c), homeostatic model assessment of insulin resistance (HOMA-IR), and quantitative insulin check index (QUICKI), triacylglycerol (TAG) and total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) ratio in the T2DM group. In fully adjusted model, the odds ratio (OR) of T2DM with serum concentrations of asprosin was approximately 1.547 (95% CI 1.293-1.850, P < 0.001) compared to the control group. Multiple stepwise regression analysis indicated that FBG and HOMA-IR were independently associated with asprosin in T2DM.

CONCLUSION

Our findings indicated that serum concentrations of asprosin are increased in patients with T2DM. Also, asprosin is correlated with insulin resistance and TC/HDL-C ratio (atherosclerotic risk factor of cardiovascular diseases) in patients with T2DM.

Asprosin: A Novel Player in Metabolic Diseases

Asprosin, a novel glucogenic adipokine, is encoded by two exons (exon 65 and exon 66) of the gene Fibrillin 1 (FBN1) and mainly synthesized and released by white adipose tissue during fasting. Asprosin plays a complex role in the central nervous system (CNS), peripheral tissues, and organs. It is involved in appetite, glucose metabolism, insulin resistance (IR), cell apoptosis, etc. In this review, we will summarize the newly discovered roles of asprosin in metabolic diseases including diabetes, obesity, polycystic ovarian syndrome (PCOS), and cardiovascular disease (CVD), which may contribute to future clinical diagnosis and treatment.