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Diabetes in the young has been traditionally defined as onset of diabetes below 35 years of age. In this age bracket, a variety of distinct types of diabetes might occur which poses a unique challenge in the diagnosis and management. Phenotypic features such as age of onset, presence of obesity and family history have traditionally been used in differentiating the various types of diabetes. With the increasing prevalence of obesity and T2DM in youth, these features have become less reliable in classifying diabetes in this age group. Along with detailed patient history and physical examination, biochemical parameters such as C-peptide and presence or absence of pancreatic autoantibodies (along with imaging studies for pancreatic pathology and genetic testing for monogenic forms of diabetes) are assuming greater importance in appropriate diagnosis and understanding the types of diabetes. C-peptide test which is a proxy for pancreatic beta cell function plays an important role in classifying type / subtypes of diabetes. When used appropriately it also helps in personalized approach to treatment and practice of Precision Diabetes.

الملخص: أهداف البحث: تعمل التمارين الرياضية على تحسين نسبة السكر في الدم بعد الأكل وحساسية الأنسولين لدى الأفراد المصابين بمرض السكري، ولكن تظل الكثافة المثلى لهذا التنظيم الأيضي غير واضحة. تهدف الدراسة الحالية إلى استكشاف تأثير كثافات التمارين المختلفة على مستويات الجلوكوز في الدم والأنسولين والببتيد سي لدى الأفراد المصابين بمرض السكري لتحديد الكثافة المثلى لتحسين هذه المؤشرات الأيضية. طريقة البحث: في هذه الدراسة المتقاطعة، شارك 25 فردا مصابا بمرض السكري في جلسات تمرين بأربع كثافات مختلفة بنسبة 50% و60% و70% و80% من أقصى معدل ضربات قلب متوقع باستخدام جهاز المشي. استمرت كل جلسة لمدة 30 دقيقة، بما في ذلك فترة إحماء لمدة 5 دقائق وفترة تهدئة لمدة 5 دقائق. تم جمع عينات الدم في أربع نقاط زمنية مميزة: أثناء الصيام، وقبل التمرين مباشرة، وبعد التمرين بـ 30 و60 دقيقة. تم تحليل هذه العينات لمعرفة مستويات الجلوكوز والأنسولين والببتيد سي. تم تقييم تأثيرات شدة التمرين على هذه المعلمات باستخدام تحليل التباين المتكرر، مع إجراء اختبارات لاحقة لتحديد الاختلافات المحددة بين الشدة. النتائج: كان متوسط أعمار المشاركين 34.88 عاما، ومتوسط طولهم 170 سم، ومؤشر كتلة الجسم 30.34 كجم/م2. لوحظ انخفاض كبير في مستويات الأنسولين والجلوكوز بعد التمرين بنسبة 70%. وعلى الرغم من ارتفاع مستويات الجلوكوز في الدم أثناء الصيام (110-115 مجم/ديسيلتر)، فقد لوحظ انخفاض كبير بعد 30 و60 دقيقة من التمرين. اقتربت مستويات الأنسولين من خط الأساس عند 70% من الشدة، من الصيام إلى 60 دقيقة بعد التمرين، مما يشير إلى استجابة إيجابية عند هذه الشدة. أظهرت مستويات الببتيد سي أيضًا تغييرات كبيرة، حيث جعل التمرين بنسبة 70% من الشدة أقرب إلى مستويات الصيام بعد 60 دقيقة من التمرين. الاستنتاجات: تسلط هذه الدراسة الضوء على أهمية شدة التمارين الرياضية في تحسين المعايير الأيضية لدى الأفراد المصابين بمرض السكري. وعلى وجه التحديد، كان 70% من الحد الأقصى لمعدل ضربات القلب المتوقع مفيدا، مما أدى إلى تحسين حساسية الأنسولين وتقليل خطر الإصابة بمرض السكري من مرحلة ما قبل السكري. Abstract: Objective: Exercise improves postprandial glycaemia and insulin sensitivity in individuals with prediabetes, but the optimal intensity for this metabolic regulation remains unclear. The current study aims to explore the impact of various exercise intensities on metabolic markers in prediabetic individuals to identify the optimal intensity for improving these indicators. Methods: In this crossover study, 25 prediabetic individuals participated in exercise sessions at 50 %, 60 %, 70 %, and 80 % intensities of their predicted maximum heart rate using a treadmill. Each session lasted for 30 min, including a 5-min warm-up and a 5-min cool-down period. Blood samples were collected at four distinct time points: during fasting, immediately before exercise, and 30 and 60 min post-exercise. These samples were analyzed for glucose, insulin, and C-peptide levels. The effects of exercise intensity on these parameters were evaluated using repeated measures ANOVA, with post hoc tests conducted to determine specific differences between the intensities. Results: The participants had an average age of 34.88 years, a mean height of 170 cm, and a BMI of 30.34 kg/m². A significant reduction in insulin and glucose levels post-exercise was observed at 70 % intensity (p ≤ 0.001). Despite high fasting blood glucose levels (110–115 mg/dL), significant reductions were noted at 30 and 60 min post-exercise (p ≤ 0.001). Insulin levels approached near baseline at 70 % intensity, from fasting (26.74 ± 20.83) to 60 min post-exercise (28.47 ± 20.79), indicating a positive response at this intensity. C-peptide levels also showed significant changes, with the 70 % intensity exercise bringing them closest to fasting levels by 60 min post-exercise. Conclusion: This study highlights the importance of exercise intensities in enhancing metabolic parameters in prediabetic individuals. Specifically, 70 % of the predicted maximum heart rate was beneficial, optimizing insulin sensitivity and potentially reducing the risk of progressing from prediabetes to diabetes.

Abstract Background In order to investigate microvascular complications in metabolic diseases, we aimed to investigate cerebral and peripheral microcirculation in relation to peripheral neuropathy and laboratory biomarkers in type 2 diabetes mellitus (T2DM) and obesity. Methods Based on the degree of neuropathy (NP), study participants (40 T2DM and 30 obese individuals) were classified into no-NP, mild-NP and severe-NP subgroups. After the injection of Technetium-99 m hexamethylpropylene amine oxime, both T2DM and obese participants underwent single-photon emission computed tomography/computed tomography ([99mTc]Tc-HMPAO SPECT/CT) and SPECT-only examinations to assess lower limb and brain perfusion; respectively. Peripheral nerve function was evaluated with a neurometer and glycaemic markers were measured from plasma in both groups. Results Compared to the obese individuals, lower extremity perfusion was significantly reduced in the diabetic subjects (p

IntroductionExercise is vital in preventing and treating obesity. Despite its importance, the understanding of how exercise influences childhood obesity at the biochemical level is limited. In this study, we explore the effects of a 16-week exercise program (EP) on body composition, physical fitness, and the blood levels of hormones related to obesity.MethodsSixteen boys with obesity (n = 16) and seventeen boys without obesity (n = 17) took part in an EP comprising sports games and aerobic and resistance exercises. We examined alterations in body composition and physical fitness. In addition, we measured circulating hormone levels, including C-peptide, resistin, insulin-like growth factor 1 (IGF-1), and growth hormone (GH), in the blood.ResultsBody fat percentage (BFP) decreased from 37.61% at pre-EP to 29.16% at post-EP in the obese group, but not in the non-obese group. The EP decreased C-peptide (4.58 ng/mL vs. 2.96 ng/mL, p < 0.001) and resistin levels (14.05 ng/mL vs. 11.06 ng/mL, p < 0.001) in the obese group. After the EP, significant improvement in IGF-1 (non-obese: 265.56 ng/mL vs. 311.81 ng/mL, p < 0.001; obese: 224.74 ng/mL vs. 272.89 ng/mL, p < 0.001) and GH levels (non-obese: 3.91 ng/mL vs. 4.80 ng/mL, p < 0.05; obese: 1.76 ng/mL vs. 2.51 ng/mL, p < 0.05) were observed in both groups. Lower C-peptide levels were associated with BFP (r = 0.447, p = 0.009) and muscle mass (r = −0.385, p = 0.02), whereas enhanced IGF-1 levels correlated with increased muscle strength (r = 0.343, p = 0.05) and cardiovascular fitness (r = 0.347, p = 0.04). Multiple linear regression analysis revealed that cardiovascular fitness variability and BFP in the obese group were determined by C-peptide (β = −0.054, p < 0.001) and IGF-1 levels (β = −2.936, p < 0.05), respectively.DiscussionExercise may induce positive effects on improvements in body composition and physical fitness, as well as on blood levels of metabolic biochemicals such as C-peptide and IGF-1, in adolescent boys with obesity.

ObjectiveDiabetic peripheral neuropathy (DPN) is a chronic complication of diabetes that can potentially escalate into ulceration, amputation and other severe consequences. The aim of this study was to construct and validate a predictive nomogram model for assessing the risk of DPN development among diabetic patients, thereby facilitating the early identification of high-risk DPN individuals and mitigating the incidence of severe outcomes.Methods1185 patients were included in this study from June 2020 to June 2023. All patients underwent peripheral nerve function assessments, of which 801 were diagnosed with DPN. Patients were randomly divided into a training set (n =711) and a validation set (n = 474) with a ratio of 6:4. The least absolute shrinkage and selection operator (LASSO) logistic regression analysis was performed to identify independent risk factors and develop a simple nomogram. Subsequently, the discrimination and clinical value of the nomogram was extensively validated using receiver operating characteristic (ROC) curves, calibration curves and clinical decision curve analyses (DCA).ResultsFollowing LASSO regression analysis, a nomogram model for predicting the risk of DPN was eventually established based on 7 factors: age (OR = 1.02, 95%CI: 1.01 - 1.03), hip circumference (HC, OR = 0.94, 95%CI: 0.92 – 0.97), fasting plasma glucose (FPG, OR = 1.06, 95%CI: 1.01 - 1.11), fasting C-peptide (FCP, OR = 0.66, 95%CI: 0.56 - 0.77), 2 hour postprandial C-peptide (PCP, OR = 0.78, 95%CI: 0.72 – 0.84), albumin (ALB, OR = 0.90, 95%CI: 0.87 – 0.94) and blood urea nitrogen (BUN, OR = 1.08, 95%CI: 1.01 - 1.17). The areas under the curves (AUC) of the nomogram were 0.703 (95% CI 0.664-0.743) and 0.704 (95% CI 0.652-0.756) in the training and validation sets, respectively. The Hosmer–Lemeshow test and calibration curves revealed high consistency between the predicted and actual results of the nomogram. DCA demonstrated that the nomogram was valuable in clinical practice.ConclusionsThe DPN nomogram prediction model, containing 7 significant variables, has exhibited excellent performance. Its generalization to clinical practice could potentially help in the early detection and prompt intervention for high-risk DPN patients.

Objective To evaluate the effects of alpha lipoic acid (ALA) on hormonal and metabolic parameters in a group of overweight/obese Polycystic Ovary Syndrome (PCOS) patients.Methods This was a retrospective study in which thirty-two overweight/obese patients with PCOS (n = 32) not requiring hormonal treatment were selected from the database of the ambulatory clinic of the Gynecological Endocrinology Center at the University of Modena and Reggio Emilia, Italy. The hormonal profile, routine exams and insulin and C-peptide response to oral glucose tolerance test (OGTT) were evaluated before and after 12 weeks of complementary treatment with ALA (400 mg/day). Hepatic Insulin Extraction (HIE) index was also calculated.Results ALA administration significantly improved insulin sensitivity and decreased ALT and AST plasma levels in all subjects, though no changes were observed on reproductive hormones. When PCOS patients were subdivided according to the presence or absence of familial diabetes background, the higher effects of ALA were observed in the former group that showed AST and ALT reduction and greater HIE index decrease.Conclusion ALA administration improved insulin sensitivity in overweight/obese PCOS patients, especially in those with familial predisposition to diabetes. ALA administration improved both peripheral sensitivity to insulin and liver clearance of insulin. Such effects potentially decrease the risk of nonalcoholic fat liver disease and diabetes in PCOS patients.

Background We evaluated changes in glycemic status, over 1 year, of coronavirus disease 2019 (COVID-19) survivors with dysglycemia in acute COVID-19. Methods COVID-19 survivors who had dysglycemia (defined by glycosylated hemoglobin [HbA1c] 5.7% to 6.4% or random glucose ≥10.0 mmol/L) in acute COVID-19 were recruited from a major COVID-19 treatment center from September to October 2020. Matched non-COVID controls were recruited from community. The 75-g oral glucose tolerance test (OGTT) were performed at baseline (6 weeks after acute COVID-19) and 1 year after acute COVID-19, with HbA1c, insulin and C-peptide measurements. Progression in glycemic status was defined by progression from normoglycemia to prediabetes/diabetes, or prediabetes to diabetes. Results Fifty-two COVID-19 survivors were recruited. Compared with non-COVID controls, they had higher C-peptide (P< 0.001) and trend towards higher homeostasis model assessment of insulin resistance (P=0.065). Forty-three COVID-19 survivors attended 1-year reassessment. HbA1c increased from 5.5%±0.3% to 5.7%±0.2% (P

Background:Diabetic neuropathy affects significant individuals worldwide and is considered a chronic complication of diabetes. However, the exact mechanisms underlying the development of diabetic neuropathy are still not fully understood. Objectives:This study investigated the involvement of vitamin D2, PTH, and C-peptide in the onset of diabetic neuropathy. Materials and Methods:This study included 120 diabetic patients and 30 healthy controls. Diabetic patients were divided into group 1 with neuropathy (N = 80) and group 2 without neuropathy (N = 40). The following data were incorporated: sex, age, diabetes duration, and BMI. Biochemical evaluations involved HbA1C, C-peptide, PTH, and vitamin D2. Results:The study’s population had a 52.2 ± 13.9 years mean age. Patients had 9.8 years average diabetes duration, were mostly overweight, and were poorly controlled (mean HbA1C = 8.8). Vitamin D2 was insufficient, particularly in diabetics, and C-peptide measures were markedly low. There were differences in the three parameters between diabetes and controls. Potential relationships among the parameters were detected namely, higher HbA1C, elder, lower vitamin D2, besides higher C-peptide and vitamin D2 levels. ROC-curve metrics for vitamin D2, PTH, and C-peptide, revealed varied diagnostic potential. All parameters were unable to distinguish between patients with or without neuropathy from healthy subjects. Conclusion:The study highlights the importance of glycemic control, insulin production, PTH, and vitamin D2 levels in the context of diabetic neuropathy. While these biomarkers show associations with neuropathy risk, their diagnostic potential is still limited. The associations between age, HbA1C levels, PTH, C-peptide levels, and vitamin D2 levels provide valuable insights into potential contributors to neuropathy risk.

Abstract Impaired insulin secretory capacity is associated with high glycemic variability in patients with type 2 diabetes (T2DM). However, there are no existing reports on the association between insulin secretory capacity and time in range (TIR). This retrospective study involved 330 T2DM admitted for diabetes education who underwent intermittently scanned continuous glucose monitoring (isCGM) and had their fasting serum C-peptide immunoreactivity (S-CPR) measured within 5 days of admission. The baseline characteristics were as follows: age, 60.2 years; glycated hemoglobin (HbA1c), 9.2%; S-CPR, 2.2 ng/mL; S-CPR index (S-CPR [ng/mL]/fasting plasma glucose [mg/dL] × 100), 1.6; and TIR, 60.3%. TIR correlated significantly with the S-CPR index, which was confirmed by multivariate analysis that included various factors such as HbA1c. Receiver operating characteristic (ROC) analysis showed that 1.88 was the optimal S-CPR index level to predict TIR ≥ 70%. In addition to HbA1c and biguanide use, the S-CPR index was a significant factor associated with TIR > 70%. S-CPR index values of ≥ 1.88 also correlated significantly with TIR > 70%. In conclusion, insulin secretory capacity is associated with TIR in Japanese T2DM, suggesting that the S-CPR index might be a potentially useful biomarker insulin secretory capacity, in association with TIR. Trial registration UMIN0000254333.

Tong Zhang,1– 3,&ast; Han Wu,1,2,&ast; Chenling Qiu,1,2 Mingxin Wang,1,2 Haiting Wang,1,2 Shunhua Zhu,1,4 Yinhai Xu,2 Qingli Huang,1,4 Shibao Li1,2 1Medical Technology School of Xuzhou Medical University, Xuzhou, Jiangsu, 221000, People’s Republic of China; 2Department of Laboratory Medicine, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221000, People’s Republic of China; 3Chuzhou Center for Disease Control and Prevention, Chuzhou City, Anhui, 239000, People’s Republic of China; 4Public Experimental Research Center of Xuzhou Medical University, Xuzhou City, Jiangsu, 221004, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Qingli Huang; Shibao Li, Email qlhuang@xzhmu.edu.cn; sdjnshlb@xzhmu.edu.cnIntroduction: Insulin and C-peptide played crucial roles as clinical indicators for diabetes and certain liver diseases. However, there has been limited research on the simultaneous detection of insulin and C-peptide in trace serum. It is necessary to develop a novel method with high sensitivity and specificity for detecting insulin and C-peptide simultaneously.Methods: A core-shell-satellites hierarchical structured nanocomposite was fabricated as SERS biosensor using a simple wet-chemical method, employing 4-MBA and DTNB for recognition and antibodies for specific capture. Gold nanorods (Au NRs) were modified with Raman reporter molecules and silver nanoparticles (Ag NPs), creating SERS tags with high sensitivity for detecting insulin and C-peptide. Antibody-modified commercial carboxylated magnetic bead@antibody served as the capture probes. Target materials were captured by probes and combined with SERS tags, forming a “sandwich” composite structure for subsequent detection.Results: Under optimized conditions, the nanocomposite fabricated could be used to detect simultaneously for insulin and C-peptide with the detection limit of 4.29 × 10− 5 pM and 1.76 × 10− 10 nM in serum. The insulin concentration (4.29 × 10− 5– 4.29 pM) showed a strong linear correlation with the SERS intensity at 1075 cm− 1, with high recoveries (96.4– 105.3%) and low RSD (0.8%– 10.0%) in detecting human serum samples. Meanwhile, the C-peptide concentration (1.76 × 10− 10– 1.76 × 10− 3 nM) also showed a specific linear correlation with the SERS intensity at 1333 cm− 1, with recoveries 85.4%– 105.0% and RSD 1.7%– 10.8%.Conclusion: This breakthrough provided a novel, sensitive, convenient and stable approach for clinical diagnosis of diabetes and certain liver diseases. Overall, our findings presented a significant contribution to the field of biomedical research, opening up new possibilities for improved diagnosis and monitoring of diabetes and liver diseases.Keywords: surface-enhanced Raman scattering, SERS, nanocomposites, insulin, C-peptide

Background The Korean Endocrine Hormone Reference Standard Data Center (KEHRS DC) has created reference standards (RSs) for endocrine hormones since 2020. This study is the first of its kind, wherein the KEHRS DC established RSs for serum C-peptide levels in a healthy Korean population. Methods Healthy Korean adults were recruited from May 2021 to September 2023. After excluding participants according to our criteria, serum samples were collected; each participant could then choose between fasting glucose only or fasting glucose plus an oral glucose tolerance test (OGTT). If their sample showed high glucose (≥100 mg/dL) or hemoglobin A1c (HbA1c) (≥5.70%), their C-peptide levels were excluded from analyzing the RSs. Results A total of 1,532 participants were recruited; however, only the data of 1,050 participants were analyzed after excluding those whose samples showed hyperglycemia or high HbA1c. Post-30-minute OGTT data from 342 subjects and post-120-minute OGTT data from 351 subjects were used. The means±2 standard deviations and expanded uncertainties of fasting, post-30-minute and 120-minute OGTT C-peptide levels were 1.26±0.82 and 0.34–3.18, 4.74±3.57 and 1.14–8.33, and 4.85±3.58 and 1.25–8.34 ng/mL, respectively. Serum C-peptide levels correlated with obesity, serum glucose levels, and HbA1c levels. Conclusion The RSs for serum C-peptide levels established in this study are expected to be useful in both clinical and related fields.

Abstract Background Growth differentiation factor 15 (GDF15) is a mitokine, the role of which, total or H-specific, in modulating energy metabolism and homeostasis in obesity-related diseases, such as metabolic dysfunction associated steatotic liver disease (MASLD), has not been fully elucidated in adult humans. We aimed to investigate the fasting and stimulated levels of GDF15, total and H-specific, glucose-dependent insulinotropic polypeptide (GIP) and C-peptide, in two physiology interventional studies: one focusing on obesity, and the other on MASLD. Methods Study 1 investigated individuals with normal weight or with obesity, undergoing a 3-h mixed meal test (MMT); and study 2, examined adults with MASLD and controls undergoing a 120-min oral glucose tolerance test (OGTT). Exploratory correlations of total and H-specific GDF15 with clinical, hormonal and metabolomic/lipidomic parameters were also performed. Results In study 1, 15 individuals were included per weight group. Fasting and postprandial total and H-specific GDF15 were similar between groups, whereas GIP was markedly higher in leaner individuals and was upregulated following a MMT. Baseline and postprandial C-peptide were markedly elevated in people with obesity compared with lean subjects. GIP was higher in leaner individuals and was upregulated after a MMT, while C-peptide and its overall AUC after a MMT was markedly elevated in people with obesity compared with lean subjects. In study 2, 27 individuals were evaluated. Fasting total GDF15 was similar, but postprandial total GDF15 levels were significantly higher in MASLD patients compared to controls. GIP and C-peptide remained unaffected. The postprandial course of GDF15 was clustered among those of triglycerides and molecules of the alanine cycle, was robustly elevated under MASLD, and constituted the most notable differentiating molecule between healthy and MASLD status. We also present robust positive correlations of the incremental area under the curve of total and H-specific GDF15 with a plethora of lipid subspecies, which remained significant after adjusting for confounders. Conclusion Serum GDF15 levels do not differ in relation to weight status in hyperlipidemic but otherwise metabolically healthy individuals. In contrast, GDF15 levels are significantly increased in MASLD patients at baseline and they remain significantly higher compared to healthy participants during OGTT, pointing to a role for GDF15 as a mitokine with important roles in the pathophysiology and possibly therapeutics of MASLD. Trial registration ClinicalTrials.gov NCT03986684, NCT04430946.

Antigen-driven T-cell proliferation is often measured using fluorescent dye dilution assays, such as the CFSE-based proliferation assay. Dye dilution assays have been powerful tools to detect human CD4+ T-cell responses, particularly against autoantigens. However, it is not known how many cells within the proliferating population are specific for the stimulating antigen. Here we determined the frequency of CD4+ T cells specific for the stimulating antigen within the antigen-responsive population of CFSE-based proliferation assays. We compared CD4+ T-cell responses to a type 1 diabetes autoantigen (proinsulin C-peptide) and to a vaccine antigen (tetanus toxoid). The TCRs expressed by antigen-responsive CD4+ T cells were sequenced, and their antigen specificity was tested functionally by expressing them in a reporter T-cell line. Responses to C-peptide were weak, but detectable, in PBMC from individuals with T1D, whereas responses to tetanus toxoid were much stronger. The frequency of antigen-specific CD4+ T cells correlated with the strength of the response to antigen in the proliferation assay. However, antigen-specific CD4+ T cells were rare among antigen-responsive CD4+ T cells. For C-peptide, an average frequency of 7.5% (1%–11%, n = 4) of antigen-responsive CD4+ T cells were confirmed to be antigen specific. In the tetanus-toxoid-stimulated cultures, on average, 45% (16%–78%, n = 5) of the antigen-responsive CD4+ T cells were tetanus toxoid specific. These data show that antigen-specific CD4+ T cells are a minority of the cells that proliferate in response to antigen and have important implications for in vitro CD4+ T-cell proliferation assays.

ABSTRACT Objective This study aimed to evaluate the association of detectable C-peptide levels with various continuous glucose monitoring (CGM) metrics and diabetes complications in patients with type 1 diabetes mellitus (T1DM). Subjects and methods Retrospective, descriptive study of 112 patients with T1DM undergoing intensive insulin therapy, categorized according to fasting C-peptide level into undetectable (

Background: The efficacy of insulin and C-peptide suppression (ICPS) test using a rapid-acting insulin analog to induce hypoglycemia in the diagnosis of insulinoma has never been studied. Objective: To compare the efficacy of using plasma C-peptide (PCP) and plasma insulin (PI) responses to the ICPS test using insulin aspart and the supervised prolonged fast (SPF) test in the diagnosis of insulinoma. Methods: The ICPS test was performed in 15 patients with insulinoma (IN) and 6 patients with non-insulinoma causes of hypoglycemia (non-IN) by intravenous infusion of insulin aspart to induce hypoglycemia. Plasma glucose (PG), C-peptide (PCP), and insulin (PI) levels were measured before and at the end of the test (end-ICPS) when the patients had hypoglycemia, defined by the presence of either PG ≤50 mg/dL with hypoglycemic symptoms or PG ≤40 mg/dL regardless of hypoglycemic symptoms. PCP and PI were measured by an immunoassay system that does not cross-react to insulin aspart (Cobas Modular Analytics e801). The SPF test was also performed in IN. Results: IN had a higher median end-ICPS PI (34.77 versus 0.58 μIU/mL, p

Key Clinical Message A comprehensive evaluation, including symptoms, medical history, C‐peptide levels, and anti‐GAD antibodies, is essential for distinguishing between diabetes' types, particularly in cases of diagnostic uncertainty. While obesity is often associated with T2DM, BMI should be viewed as a factor rather than a criterion for the exclusion of diabetes type.

Abstract Background Sarcopenia, an age-related disorder characterized by loss of skeletal muscle mass and function, is recently recognized as a complication in elderly patients with type 2 diabetes mellitus (T2DM). Skeletal muscles play a crucial role in glycemic metabolism, utilizing around 80% of blood glucose. Accordingly, we aimed to explore the relationship between glucose metabolism and muscle mass in T2DM. Methods We employed the AWGS 2019 criteria for diagnosing low muscle mass and 1999 World Health Organization (WHO) diabetes diagnostic standards. This study included data of 191 individuals aged 60 and above with T2DM of Shanghai Pudong Hospital from November 2021 to November 2022. Fasting C-peptide (FPCP), fasting plasma glucose (FPG), 2-hour postprandial plasma glucose (PPG) and postprandial 2-hour C-peptide (PPCP), glycated hemoglobin A1c (HbA1c), glycated albumin (GA), serum lipids spectrum, renal and hepatic function, hemoglobin, and hormone were measured. Based on the findings of univariate analysis, logistic regression and receiver operating characteristic (ROC) curves were established. Results Participants with low muscle mass had significantly lower alanine and aspartate aminotransferase, and both FPCP and PPCP levels (P

Lina Chang,&ast; Xiaohui Ma,&ast; Menghua Yuan,&ast; Li Ding, Yian Gu, Lili Liu, Yan Li, Hua Shu, Ming Liu, Qing He Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Qing He; Ming Liu, Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, 300052, People’s Republic of China, Email heqing202301@tmu.edu.cn; mingliu@tmu.edu.cnPurpose: Understanding factors that influence blood glucose levels in patients with type 2 diabetes mellitus (T2DM) is crucial for managing hyperglycemia. Currently, there is no standardized interpretation method for glucagon levels in oral glucose tolerance test (OGTT). This study aims to assess the relationship between the lowest glucagon/highest C-peptide ratio (Lglc/Hcp) in OGTT and glucose control levels in T2DM.Patients and Methods: Clinical data from 120 patients with T2DM were examined to compare the correlations of Lglc/Hcp and other pancreatic islet function-associated indices with fasting blood glucose (G0), glucose at 120 minutes in OGTT (G120), hemoglobin A1c (HbA1c), and the area under the glucose curve in OGTT (AUCglu). Additionally, the study investigated difference in Lglc/Hcp between patient groups based on the highest blood glucose levels (Hglu) in OGTT (Hglu ≥ 16.7 mmol/L vs Hglu < 16.7 mmol/L).Results: The generalized linear model suggested that Lglc/Hcp significantly correlated with G0 (B = 0.85, P < 0.001), G120(B = 1.46, P < 0.001), HbA1c (B = 0.67, P < 0.001), and AUCglu (B = 3.46, P < 0.001). This correlation surpassed C-peptide and glucagon-related parameters, even after adjusting for confounding factors. Furthermore, Lglc/Hcp was notably higher in patients with Hglu ≥ 16.7 mmol/L compared to those with Hglu < 16.7 mmol/L (Z = − 3.71, p < 0.001).Conclusion: Lglc/Hcp in OGTT closely relates to blood glucose control in patients with T2DM, potentially reflecting the overall pancreatic islet function in regulating glucose levels. Moreover, inhibiting glucagon secretion may be a crucial consideration for patients requiring insulin treatment. Keywords: C-peptide, glucose control, glucagon, type 2 diabetes mellitus

Type 1 diabetes (T1D) is an autoimmune disease initiated by genetic predisposition and environmental influences, which result in the specific destruction of insulin‐producing pancreatic β‐cells. Currently, there are over 1.6 million cases of T1D in the United States with a worldwide incidence rate that has been increasing since 1990. Here, we examined the effect of Cornus officinalis (CO), a well‐known ethnopharmacological agent, on a T1D model of the non‐obese diabetic (NOD) mouse. A measured dose of CO extract was delivered into 10‐week‐old NOD mice by oral gavage for 15 weeks. T1D incidence and hyperglycemia were significantly lower in the CO‐treated group as compared to the water gavage (WT) and a no handling or treatment control group (NHT) following treatment. T1D onset per group was 30%, 60% and 86% for the CO, WT and NHT groups, respectively. Circulating C‐peptide was higher, and pancreatic insulitis was decreased in non‐T1D CO‐treated mice. Our findings suggest that CO may have therapeutic potential as both a safe and effective interventional agent to slow early stage T1D progression.

There are multiple disease-modifying immunotherapies showing the potential of preventing or delaying the progression of type 1 diabetes (T1D). We designed and performed this systematic review and meta-analysis to gain an overview of what a role immunotherapy plays in the treatment of T1D. We searched PubMed, Embase and Cochrane Central Register of Controlled Trials (CENTRAL) from inception to December 2023. We included clinical trials of immunotherapy conducted in patients with T1D that reported the incidence of hypoglycemia or changes from baseline in at least one of following outcomes: 2 h and 4 h mixed-meal-stimulated C-peptide area under the curve (AUC), fasting C-peptide, daily insulin dosage, glycated hemoglobin (HbA1c) and fasting plasma glucose (FPG). The results were computed as the weighted mean differences (WMDs) or odds ratios (ORs) and 95% confidence intervals (CIs) in random-effect model. In all, 34 clinical trials were included. When compared with control groups, 2 h C-peptide AUC was marginally higher in patient treated with nonantigen-based immunotherapies (WMD, 0.04nmol/L, 95% CI, 0.00–0.09 nmol/L, P=0.05), which was mainly driven by the effects of T cell-targeted therapy. A greater preservation in 4 h C-peptide AUC was observed in patients with nonantigen-based immunotherapies (WMD, 0.10nmol/L, 95% CI, 0.04–0.16 nmol/L, P=0.0007), which was mainly driven by the effects of tumor necrosis factor α (TNF-α) inhibitor and T cell-targeted therapy. After excluding small-sample trials, less daily insulin dosage was observed in patient treated with nonantigen-based immunotherapies when compared with control groups (WMD, −0.07units/kg/day, 95% CI, −0.11 to −0.03units/kg/day, P=0.0004). The use of antigen-based immunotherapies was also associated with a lower daily insulin dosage versus control groups (WMD, −0.11units/kg/day, 95% CI, −0.23 to −0.00units/kg/day, P=0.05). However, changes of HbA1c or FPG were comparable between nonantigen-based immunotherapies or antigen-based immunotherapies and control groups. The risk of hypoglycemia was not increased in patients treated with nonantigen-based immunotherapies or patients treated with antigen-based immunotherapies when compared with control groups. In conclusion, nonantigen-based immunotherapies were associated with a preservation of 2 h and 4 h C-peptide AUC in patients with T1D when compared with the controls, which was mainly driven by the effects of TNF-a inhibitor and T cell-targeted therapy. Both nonantigen-based immunotherapies and antigen-based immunotherapies tended to reduce the daily insulin dosage in patients with T1D when compared with the controls. However, they did not contribute to a substantial improvement in HbA1c or FPG. Both nonantigen-based immunotherapies and antigen-based immunotherapies were well tolerated with not increased risk of hypoglycemia in patients with T1D.

Background We assessed whether a sustained period of intensive glucose control with hybrid closed-loop for 12 months following diagnosis of type 1 diabetes in children and adolescents can preserve C-peptide secretion compared to standard insulin therapy. Methods In an open-label, multicentre, randomised, parallel trial, youth aged 10–16.9 years were randomised within 21 days of type 1 diabetes diagnosis to hybrid closed-loop or standard insulin therapy (control). Primary end point was the difference in mixed-meal C-peptide area under the curve 12 months post diagnosis. Key secondary end points included time spent in target glucose range, glycated haemoglobin and time spent below target glucose range at 12 months. Analysis was by intention to treat. The Closed Loop from Onset in Type 1 Diabetes consortium secured external funding for participants to continue on beyond 12 months, but the funding by National Institute for Health and Care Research and the results reported here refer only to the 12 months follow-up. Results We randomised 97 participants (mean ± standard deviation age 12 ± 2 years), 51 to closed-loop and 46 to control therapy. There was no difference in C-peptide area under the curve at 12 months between groups [geometric mean (interquartile range) closed-loop (n = 46): 0.35 pmol/ml (0.16, 0.49) vs. control (n = 37): 0.46 pmol/ml (0.22, 0.69); mean adjusted difference –0.06 (95% confidence interval –0.14 to 0.03); p = 0.19]. The proportion of time in target range 3.9–10.0 mmol/l based on 14-day masked LibrePro (Abbott Diabetes Care, Maidenhead, UK) sensor glucose data at 12 months was 10 percentage points (95% confidence interval 2 to 17) higher in the closed-loop group (64 ± 14%) compared to control group (54 ± 23%). Arithmetic mean glycated haemoglobin A1c was lower in the closed-loop group by 4 mmol/mol (0.4%) [95% confidence interval 0 to 8 mmol/mol (0.0% to 0.7%)] at 12 months. The mean difference in time spent 10.0 mmol/l was 11 percentage points (95% CI 3 to 19 percentage points) lower in the CL group compared to the control group at 12 months. Glucose variability measured by standard deviation (SD) was similar between CL and control groups, while coefficient of variation of glucose was 4 percentage points higher in the CL group at 12 months (95% CI 1 to 8 percentage points). The primary end point was similar in a per-protocol analysis using data from randomised participants in the CL group with at least 60% CL use and those in the control group who did not start insulin pump therapy. Total daily insulin dose was similar between treatment groups, but there was a greater proportion of basal insulin (mean ± SD closed-loop 0.52 ± 0.31 U/kg/day, control 0.37 ± 0.26 U/kg/day) to bolus insulin (mean ± SD closed-loop 0.44 ± 0.22 U/kg/day, control 0.46 ± 0.23 U/kg/day) in the CL group at 12 months. Blood pressure, lipid profile and BMI percentile were similar between treatment groups. In the CL group, median CL use was 66% (IQR 44–80) over the 12-month period. In the control group, 10% of participants (n = 4) were using insulin pump therapy and 57% (n = 21) were using a flash or real-time continuous glucose sensor at 12 months post diagnosis. Three severe hypoglycaemic events occurred in the CL group (two participants), and one in the control group; one DKA occurred in the CL group and none in the control group. The number of other AEs (CL group 34, control group 37) and SAEs (CL group 2, control group 4) was similar between groups. Responses to the Pediatric Quality of Life Inventory (PedsQL), hypoglycaemia fear survey (HFS), problem areas in diabetes (PAID) and Strengths and Difficulties Questionnaires (SDQs) were similar between treatment groups in both children and parents at 12 months. Scores for the INSPIRE (INsulin Dosing Systems: Perceptions, Ideas, Reflections and Expectations) questionnaire were high in children, teenagers and parents, suggesting positive expectancies regarding automated insulin delivery in this population. In-depth interviews of 18 youths and 21 parents with ≥ 12 months’ experience of using CL technology were undertaken. Interviews explored the impact of using CL systems on diabetes management practices and everyday family life. As reported by Lawton et al. Participants reported very few disruptions to their lives when using a closed-loop system. Reports of family conflict were minimal as the closed-loop enabled dietary flexibility and glucose levels to be checked effortlessly. Adolescents described doing ‘normal’ activities without worrying about high or low glucose, and parents reported allowing them to do so unsupervised because the closed-loop would regulate their glucose and keep them safe. Some adolescents expressed concerns about the visibility of components and, to avoid stigma, described curtailing activities such as swimming. Participants described how the closed-loop enabled adolescents to be in control of, or create distance from, their diabetes. Lawton J, Kimbell B, Rankin D, Ashcroft NL, Varghese L, Allen JM, et al.; CLOuD Consortium. Health professionals’ views about who would benefit from using a closed-loop system: a qualitative study. Diabet Med: J Br Diabet Assoc 2020;37(6):1030–7. Interviews of multidisciplinary healthcare professionals (n = 22) providing support to trial participants explored the benefits, issues and challenges arising from introducing and using CL systems to support diabetes self-management. Lawton et al. reported that interviewees described how, compared with other insulin regimens, teaching and supporting individuals to use a closed-loop system could be initially more time-consuming. However, they also noted that after an initial adjustment period, users had less need for initiating contact with the clinical team compared with people using pumps or multiple daily injections. Interviewees highlighted how a lessened need for ad hoc clinical input could result in new challenges; specifically, they had fewer opportunities to reinforce users’ diabetes knowledge and skills and detect potential psychosocial problems. Lawton et al. (2020) We explored health professionals’ views about who would benefit from using a CL system. Interviewees described holding strong assumptions about the types of people who would use the technology effectively prior to the trial. Interviewees described changing their views as a result of observing individuals engaging with the CL system in ways they had not anticipated. This included educated, technologically competent individuals who over-interacted with the system in ways which could compromise glycaemic control. Other individuals, who health professionals assumed would struggle to understand and use the technology, were reported to have benefited from it because they stood back and allowed the system to operate without interference. Interviewees concluded that individual, family and psychological attributes cannot be used as pre-selection criteria and ideally all individuals should be given the chance to try the technology. Conclusions The CLOuD study demonstrates that CL glucose control over a period of 12 months does not slow the decline in C-peptide secretion in children and adolescents with new-onset type 1 diabetes. Mean time in range was 10 percentage points higher and mean HbA1c was 0.4% (4 mmol/mol) lower in the CL group compared with the control group at 12 months, but these end points did not reach the pre-specified significance thresholds and it is possible that a greater improvement in glucose control with attainment of normoglycaemia could prevent the decline in C-peptide secretion. Further work may be needed to definitively rule out a role of glycaemic burden in the decline of C-peptide secretion. Total daily exogenous insulin requirements, a surrogate marker of residual insulin secretion, were similar between groups at all time points after diagnosis. This comparison may be hampered by any between-group differences in glycaemic control. It is likely that factors other than glycaemic control, such as autoimmune response, determine the rate of C-peptide decline following diagnosis of type 1 diabetes. It is possible that other factors act in concert with dysglycaemia on C-peptide secretion. The present study demonstrates that hybrid CL is effective in new-onset type 1 diabetes in youth and can safely accommodate the variability in exogenous insulin requirements which occur with beta-cell recovery post diagnosis. Glycaemic control was sustained over 12 months in the CL group, whereas glycaemic control started to deteriorate in the control group at 6 to 9 months after diagnosis. At 12 months post diagnosis, only 56% of youth in the control group (78% in the CL group) were able to achieve a HbA1c of

Abstract Background Accompanying islet α- and β-cell dysregulation in type 2 diabetes (T2D) at the microscopic scale, alterations in body composition at the macroscopic scale may affect the pathogenesis of T2D. However, the connections between body composition and islet α-cell and β-cell functions in T2D have not been thoroughly explored. Methods For this cross-sectional study, we recruited a total of 729 Chinese Han patients with T2D in a consecutive manner. Dual-energy X-ray absorptiometry (DXA) was used to measure body composition, which included total bone-free mass, total fat and lean mass, trunk fat and lean mass and limb fat and lean mass. Every patient underwent an oral glucose tolerance test to simultaneously detect glucose, C-peptide and glucagon. The indices of islet α-cell function included fasting glucagon levels and the area under the curve of glucagon after a challenge (AUCglucagon), while the indices of β-cell function included the insulin sensitivity index derived from C-peptide (ISIC-peptide) and the area under the curve of C-peptide after a challenge (AUCC-peptide). Results Among all patients, fat mass, especially trunk fat mass, was significantly correlated with ISIC-peptide and AUCC-peptide levels (r = − 0.330 and 0.317, respectively, p

Objective To analyze the diagnostic value of combined detection of nerve F-wave conduction velocity(CV) and fasting C-Peptide (FC-P) level in evaluating diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes mellitus (T2DM). Methods A total of 30 T2DM patients with DPN who were treated at Ma’anshan People's Hospital from September 2020 to June 2022 were selected as the observation group, 30 T2DM patients without DPN were selected as the control group, and 30 healthy volunteers from the same period were recruited as the blank group. The levels of FC-P, 2 h postprandial C peptide (PC-P), fasting blood glucose (FBG), 2 h postprandial blood glucose (PBG) and glycosylated hemoglobin (HbA1c) were compared among the three groups. Nerve conduction velocity (including sensory CV, motor CV) and F-wave CV were compared among the three groups. Binary logistic regression was used to analyze the risk factors of DPN in T2DM patients. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of various indicators for the occurence of DPN. Results Compared with control group and blank group, the serum levels of FC-P and PC-P were lower, and the levels of FBG, PBG and HbA1c were higher in the observation group (P＜0.05). The serum levels of FC-P and PC-P in the control group were lower than those in the blank group, and the levels of FBG, PBG and HbA1c in the control group were higher than those in the blank group (P＜0.05). Sensory CV, motor CV and F-wave CV were the slowest in the observation group, followed by the control group, and the fastest in the blank group (P＜0.05). Binary logistic regression analysis showed that slow F-wave CV of median nerve and low FC-P level were the risk factors for DPN in diabetic patients. When median nerve F-wave CV (cut-off point was 48.05 m/s) combined with FC-P (cut-off point was 1.61 pmol/L), the area under ROC of DPN in patients with early diagnosis of diabetes was 0.819, the sensitivity was 82.60% and the specificity was 88.40%. Conclusion The combined detection of nerve F-wave CV and FC-P level can improve the predictive value of DPN in T2DM patients, and can be used for the diagnosis of early DPN patients.

Abstract Background New-onset diabetes in youth encompasses type 1 diabetes, type 2 diabetes, monogenic diabetes, and rarer subtypes like Type B insulin resistance syndrome and ketosis-prone atypical diabetes in African populations. Some cases defy classification, posing management challenges. Here, we present a case of a unique, reversible diabetes subtype. Case presentation We describe an adolescent African girl recently diagnosed with systemic lupus erythematosus. At age 15, she presented with ketoacidosis, HbA1c of 108.7 mmol/mol (12.1%), and positive anti-insulin antibodies. Initially diagnosed with type 1 diabetes, insulin was prescribed. Due to the presence of obesity and signs of insulin resistance, we added metformin. Concurrently, she received treatment for lupus with hydroxychloroquine, mycophenolate mofetil, and prednisone. After discharge, she stopped insulin due to cultural beliefs. Five months later, her glycemia and HbA1c normalized (37 mmol/mol or 5.5%) without insulin, despite corticosteroid therapy and weight gain. Autoantibodies normalized, and lupus activity decreased. Genetic testing for monogenic diabetes was negative, and the type 1 genetic risk score was exceptionally low. Conclusions We present a complex, reversible diabetes subtype. Features suggest an autoimmune origin, possibly influenced by overlapping HLA risk haplotypes with lupus. Lupus treatment or immunomodulation may have impacted diabetes remission. Ancestry-tailored genetic risk scores are currently designed to improve diagnostic accuracy.

Jianting Li,1,2 Zhenhua Dong,2 Xiaoli Wang,2 Xin Wang,2 Lulu Wang,2 Shuguang Pang1– 3 1Department of Endocrinology, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, 250013, People’s Republic of China; 2Department of Endocrinology, Central Hospital Affiliated to Shandong First Medical University, Jinan, 250013, People’s Republic of China; 3Department of Clinical Medicine, Weifang Medical College, Weifang Medical College, Weifang, People’s Republic of ChinaCorrespondence: Shuguang Pang, Email shuguangpang@163.comBackground and Aim: Controlling the risk factors was the most effective strategy to prevent diabetic retinopathy (DR). This study aimed to recognize the risk factors of DR, and explores whether the effect of those factors is modified by diabetes mellitus (DM) duration.Methods: A total of 1058 DM patients with information about DR assessment were included. DR was measured by a complete ophthalmic examination and was classified as having one or more distinct microaneurysms in the eyes. Data from the lab and clinical factors were gathered. Multivariate logistic analysis was used to examine the risk factors, and the best-fitting model was selected by a backward stepwise based on A1C.Results: In the current study, 274 (25.9%) patients developed DR. In the entire subjects, baseline age, the level of C-peptide, and urinary creatinine were all presented as protective effects of DR, whose odds ratios (ORs) and 95% confidence intervals (CIs) were 0.79 (0.62, 0.99), 0.75 (0.61, 0.91), and 0.70 (0.52, 0.93), respectively. Conversely, systolic pressure (SBP), urinary albumin, and BUN/Cr ratio were the important risk factors for DR with ORs (95% CIs) 1.21 (1.01, 1.46), 1.55 (1.30, 1.84), and 1.33 (1.11, 1.59), respectively. In stratification analysis, females with higher SBP would be more likely to develop DR in the short-duration group, while C-peptide and urinary creatinine showed protective effects in the long-duration group. BUN/Cr ratio all presented as a risk factor, with ORs 1.38 (p = 0.041) and 1.33 (p = 0.014) in short- and long-duration groups, respectively.Conclusion: Although renal functions presented a significant association with DR in all DM patients, the risk factors of DR varied widely in different disease-duration subjects. Target strategies to prevent DR should be put forward individually, considering the patient’s DM duration. Improving the BUN/Cr ratio may be beneficial to delaying DR.Keywords: diabetic retinopathy, clinical factors, C-peptide, BUN/Cr ratio, risk factors analyses

Abstract Background C-peptide is considered a peptide with active function in the body, which can affect people’s health. However, the results of previous studies on the possible association of C-peptide with the risk of cardiometabolic disorders have not been fully understood. This systematic review and meta-analysis aimed to investigate the association between serum C-peptide level and the risk of cardiovascular disease (CVD) events. Methods The various important databases, including PubMed, Scopus, and Web of Science, were searched comprehensively to November 2022 to identify the relevant studies. The HR(95% CI) or OR(95% CI) for observational studies were extracted and converted into log HR or log OR and their standard deviation(SD) was computed. A random-effects model with an inverse variance weighting method was conducted, to calculate the pooled effect size. Results Sixteen observational studies, including one case-control study, eight cohort studies, and seven cross-sectional studies were included in the current meta-analysis. The sample size ranged from 90 to 7030, with an age range from 12 to 85 years. During the follow-up time (ranging from 5 to 17 years), 4852 CVD events occurred. Based on cohort and case-control studies, the pooled results showed no significant association between serum C-peptide with CVD events risk (RR = 1.02;95%CI:0.91–1.15, I2 = 34.7%; P-heterogeneity = 0.140). For cross-sectional studies, the pooled results indicated a positive association between serum C-peptide and the odds of CVD outcomes (OR = 1.35;95%CI:1.04–1.76, I2 = 83.6%; P-heterogeneity

Background: Insulin resistance (IR) and diabetes are common chronic conditions amongst elderly patients, that may lead to increase in abdominal adipose tissue deposits and pancreatic size. Methods: A cross-sectional study was conducted in the geriatric OPD in a tertiary care hospital for a period of six months to correlate fasting C-peptide levels, abdominal adipose tissue thickness, and pancreatic size in poorly controlled diabetic elderly patients. Diabetic elderly patients with HBA1c level >7 % were enrolled with their consent. Body mass index (BMI), fasting C-peptide, abdominal adipose tissue thickness and pancreatic size were measured using standard laboratory techniques. The data obtained were assessed categorically and represented as [n (%)]. T-test was used to compare the two groups (p < 0.05). Results: A total of 101 patients were enrolled. The study results showed no significant correlation between subcutaneous fat and pre-peritoneal fat thickness; and fasting c-peptide levels (p = 0.801, p = 0.316). However, there was a significant correlation between the fasting c-peptide levels and pancreatic size (p = 0.001). It was also observed the study participants had a decreased pancreatic size, with the mean size being 4.837 cm in males, and 4.4418 cm in females. Conclusion: Intra-peritoneal fat thickness and pancreatic size can be used as surrogate marker for IR along with C-peptide. All elderly with uncontrolled type 2 diabetes mellitus behaving like type 1 diabetes mellitus needs further evaluation and pathogenic process must be explored. Sarcopenic obesity evaluation must be a part of uncontrolled type diabetes mellitus management.

BackgroundEvidence of vitamin D status and cardiometabolic health in adults with type 2 diabetes mellitus (T2DM) is still limited. This study aimed to investigate the association between vitamin D status and cardiometabolic risk factors among adults with T2DM in Shenzhen, China.MethodsThis cross-sectional study included 164 adults (aged ≥18 years) with T2DM who were hospitalized at Peking University Shenzhen Hospital from March 1, 2023, to May 31, 2023. Serum 25-hydroxyvitamin D [25(OH)D] concentration, the active marker of vitamin D, and three major cardiometabolic risk factors including blood pressure (BP), glucose metabolism-related indicators, and blood lipid profiles were collected. Vitamin D deficiency (VDD) was defined as 25(OH)D < 20 ng/mL. Correlation, Regression, and Logistic analysis were applied to verify the association among serum 25(OH)D concentration, VDD, and 11 cardiometabolic risk factors.ResultsMedian 25(OH)D concentration was 21.78 [interquartile range (IQR)=17.51-28.05] ng/mL. The prevalence of VDD was 40.24%. Serum 25(OH)D concentration was significantly negatively correlated with diastolic BP (DBP) and glycated hemoglobin A1c (HbA1c) rather than systolic BP, plasma glucose, plasma C-peptide, and blood lipid profiles among adults with T2DM in both correlation and linear regression analysis. Furthermore, the adjusted odd ratio for poor DBP control (≥90 mmHg) of T2DM patients with VDD was 3.164 (95% confidence interval=1.303, 7.683; P=0.011) compared to those without VDD.ConclusionIn China, VDD was highly prevalent among adults with T2DM and associated with greater cardiovascular risk factors, especially with increased chances of uncontrolled DBP. These findings suggest that vitamin D levels should be monitored in T2DM patients, especially those with high DBP.

Latent autoimmune diabetes in adults (LADA) according to various sources is from 4 to 12% of all cases of type 2 diabetes mellitus (T2DM). Its uniqueness lies in the simultaneous combination of autoantibodies to β-cells (characteristic of T1DM) and the possibility of treatment with oral hypoglycemic drugs (characteristic of T2DM) for at least 6 months. This is based on the pathogenesis common for T1DM and T2DM — the presence of an autoimmune reaction with the simultaneous involvement of adaptive and innate immunity, as well as, to a lesser extent, insulin resistance and a number of components of the metabolic syndrome. LADA has more in common with T1DM — the same stages in the development of the disease, from genetic predisposition to the undoubted development of insulin dependence, the difference lies in the duration of each of the periods and the age of manifestation. LADA is characterized by an older age of manifestation of 30–35 years and a slower rate of destruction of β-cells. This article presents data on the diagnosis, progress of LADA, its similarities and differences with other types of DM, and immunological features. The article also analyzes the modern approach to the treatment of patients with LADA and promising methods of treatment. The search for information was processing in published sources attached to the search engines PubMed, Google Scholar, Scopus, Web of Science, eLibrary.ru over the past 10 years. The following medical subject headings were used: latent autoimmune diabetes in adults, diabetes mellitus type 1 and 2, immunology, pancreas, genetic, treatment in various combinations using OR and AND logical operators.

BACKGROUND: Type 1 diabetes mellitus (T1D) is an autoimmune disorder that leads to pancreatic β-cells destruction and progressive decrease of insulin secretion. Specific islet autoantibodies (AAbs) are the main diagnostic marker of T1D. Residual β-cell function, as measured by C-peptide, has repeatedly been demonstrated to be clinically important.AIM: To study the frequency and levels of residual C-peptide secretion and persistence of pancreatic AAbs in children with T1D with different duration and age of manifestation of the disease.MATERIALS AND METHODS: The levels of C-peptide and AAbs to ZnT8 (zinc transporter 8), AAbs to IA-2 (Insulinoma Antigen 2), AAbs to GAD (Glutamate Decarboxylase), IAA (insulin autoantibodies) were measured. Patients were divided into 3 groups depending on the duration of T1D (1st — 5 years) and age of manifestation (A — prepubertal and B — puberty).RESULTS: The median duration of T1D was 1.8 [0,8;3,9], 76.3% out of 1333 patients were seropositive, 40% had residual levels of C-peptide. With disease duration there were a decrease in AAbs+: 1st group 74%, 2nd group 69%, and 3rd group 48%. In all groups, percentage of patients with positive levels of one or more AAbs was significantly higher in children with T1D manifestation at puberty. GADA and ZnT8A were more common in the first year of the disease. IA-2A were observed with the same frequency in the group of adolescents. IAA were more common in patients at prepubertal age. An undetectable level of C-peptide was observed significantly higher in children with T1D manifestation in prepubertal age (p

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a heterogeneous disease. Determination of different T2DM phenotypes will improve the prediction of metabolic disorders, the risk of complications and individual diabetes therapy.AIM: To identify clusters of T2DM in patients with different duration of diabetes with a study of the frequency of diabetic complications and drug therapy in the Novosibirsk region.MATERIALS AND METHODS: The study was carried out at Diamodul in the period 2013–2017 in the Novosibirsk region. K-means cluster analysis was performed in 2805 T2DM patients aged 44 to 75 years with a duration of diabetes of 7.84±6.53 years based on 5 variables — HbA1c, age at diagnosis, BMI, C-peptide, sex.RESULTS: Cluster analysis identified three clusters: cluster 1 in 1003 patients (35.7%) with preserved β-cell function, age of T2DM diagnosis 51.72±8.29 years and BMI 33.50±5.74 kg/m2, in men there was a 27% higher risk of developing diabetic nephropathy compared to women. Cluster 2 in 432 patients (15.4%) with increased function of β-cells, the age of diagnosis of T2DM was older — 52.91±7.75 years, patients had a higher BMI of 35.64±7.21 kg/m2 and more high diastolic blood pressure, earlier development of diabetic retinopathy, nephropathy and polyneuropathy, and better response to metformin therapy and combined therapy with metformin and sulfonylurea. Cluster 3 in 1370 patients (48.8%) with reduced function of β-cells, the age of diagnosing T2DM was younger — 49.63±8.32 years, patients had a lower BMI of 33.09±6.36 kg/m2 and had longer diabetes, high fasting glucose levels, males were associated with a higher risk of developing diabetic nephropathy (by 26%) compared with women, the first line of therapy was insulin therapy in 52.8% of patients.CONCLUSION: The conducted study in T2DM patients with different duration of diabetes confirmed the possibility of using cluster analysis to identify phenotypes of T2DM in the Russian population by five variables (HbA1c, age at the time of diagnosis, BMI, C-peptide, gender). A high incidence of early development of diabetic polyneuropathy, nephropathy and retinopathy was revealed in a cluster with increased function of β-cells, male gender was risk factor for diabetic nephropathy and polyneuropathy.

Background: Emerging evidence has reported significant associations of prenatal air pollution exposure with neurodevelopmental delay in offspring. Sensitive exposure windows and the modifiable factor remain elusive. Objective: We aim to identify sensitive windows of air pollution during pregnancy on neurodevelopmental delay, and examine whether cord blood C-peptide mediates the relationship. Methods: This study included 7438 mother-newborn pairs in Hefei, China, from 2015 to 2021. Weekly exposure to particulate matter of aerodynamic diameter

Background: High altitude exposure triggers a series of physiological changes to maintain homeostasis. Although longer-term (days to years) acclimatization processes are well studied, less is known about the physiological changes upon rapid ascent. We took advantage of Peru’s geography to measure the first physiological changes following rapid transport from a low to a high-altitude environment among lowlanders. Methods: Blood glucose, insulin, C-peptide, and salivary cortisol among healthy lowland Peruvians were measured before and after glucose ingestion at 40 m and upon arrival at 3470 m. Resting heart rate, blood oxygen saturation, and blood pressure were also monitored. Results: At high altitude, we find a significant (p

Kai-Fang Hua,1,2 Bo-Yang Jing,3 Yan-Hui Wu1,4 1Department of Endocrinology, Xiang’an Hospital of Xiamen University, Xiamen, Fujian, People’s Republic of China; 2School of Medicine, Xiamen University, Xiamen, Fujian, People’s Republic of China; 3Hai Yuan College, Kunming Medical University, Kunming, Yunnan, People’s Republic of China; 4National Metabolic Management Center, Xiang’an Hospital of Xiamen University, Xiamen, Fujian, People’s Republic of ChinaCorrespondence: Yan-Hui Wu, Department of Endocrinology, Xiang’an Hospital of Xiamen University, 2000 Xiang’ an East Road, Xiamen, Fujian, 361102, People’s Republic of China, Tel +8613089998806, Email mabelwyh@163.comPurpose: This study aimed to further quantify the relationship between insulin antibodies (IAs) and the 2-hour insulin to C-peptide molar ratio (2h-ICPR) using a multiple linear regression model in T2DM patients.Methods: A total of 274 T2DM patients from April 2019 to December 2022 in Xiang’an Hospital of Xiamen University were included in this study. Multiple Linear Model Fitting was conducted on the candidate independent variables (age, BMI, HbA1c, and 2h-ICPR) for the multiple linear regression. The linear relationship between insulin antibodies (IAs) and the significant independent variables was presented by making multiple linear regression equations.Results: The total demographic characteristics of the included patients were as follows: age (51.92± 13.10 years), BMI (24.94± 3.99 kg/m2), HbA1c (9.70± 2.39%), 2h-ICPR (0.12± 0.11), and IAs (0.37± 1.12COI). Linear relationships of independent variables: age (r=0.163, p=0.007), 2h-ICPR (r=0.259, p=0.001), BMI (r=0.007, p=0.907) and 2h-ICPR (r=0.092, p=0.129). Multiple linear regression: age (unstandardized β=0.014, 95% CI: 0.004– 0.024, p=0.004), 2h-ICPR (unstandardized β=2.758, 95% CI: 1.555– 3.962, p≤ 0.001). The regression equation: .Conclusion: The quantitative relationship between 2h-ICPR and insulin antibodies was . 2h-ICPR can be a preliminary screening indicator for insulin antibody testing in patients with type 2 diabetes.Keywords: insulin, insulin antibodies, C-peptide, multiple linear regression model

Abstract Background C‐peptide therapy exerts several positive actions on nerves, vasculature, smooth muscle relaxation, kidney function and bone. To date, the role of C‐peptide in preventing type 1 diabetes‐related muscle atrophy has not been investigated. Our aim was to evaluate if C‐peptide infusion prevents muscle wasting in diabetic rats. Methods Twenty‐three male Wistar rats were randomly divided into three groups: normal control group, diabetic group and diabetic group plus C‐peptide. Diabetes was induced by streptozotocin injection, and C‐peptide was administered subcutaneously for 6 weeks. The blood samples were obtained at baseline, before streptozotocin injection and at the end of the study to assess C‐peptide, ubiquitin and other laboratory parameters. We also tested the ability of C‐peptide to regulate the skeletal muscle mass, the ubiquitin–proteasome system, the autophagy pathway as well as to improve muscle quality. Results C‐peptide administration reversed hyperglycaemia (P = 0.02) and hypertriglyceridaemia (P = 0.01) in diabetic plus C‐peptide rats compared with diabetic control rats. The diabetic‐control animals displayed a lower weight of the muscles in the lower limb considered individually than the control rats and the diabetic plus C‐peptide rats (P = 0.03; P = 0.03; P = 0.04; P = 0.004, respectively). The diabetic‐control rats presented a significantly higher serum concentration of ubiquitin compared with the diabetic plus C‐peptide and the control animals (P = 0.02 and P = 0.01). In muscles of the lower limb, the pAmpk expression was higher in the diabetic plus C‐peptide than the diabetic‐control rats (in the gastrocnemius, P = 0.002; in the tibialis anterior P = 0.005). The protein expression of Atrogin‐1 in gastrocnemius and tibialis was lower in the diabetic plus C‐peptide than in diabetic‐control rats (P = 0.02, P = 0.03). After 42 days, the cross‐sectional area in the gastrocnemius of the diabetic plus C‐peptide group had been reduced by 6.6% while the diabetic‐control rats had a 39.5% reduction compared with the control animals (P = 0.02). The cross‐sectional area of the tibialis and the extensor digitorum longus muscles was reduced, in the diabetic plus C‐peptide rats, by 10% and 11%, respectively, while the diabetic‐control group had a reduction of 65% and 45% compared with the control animals (both P

Abstract Background The conclusion between Connecting peptide (C-peptide) and diabetic chronic complication was controversial. The purpose of this study is to explore the possible association between average C-peptide with diabetic retinopathy (DR) progression in Chinese patients with type 2 diabetes. Methods This is a retro-prospective study. 622 patients with type 2 diabetes were included. DR was evaluated using non-mydriatic fundus photography and DR progression was defined as any deterioration of either eye. Fasting and postprandial c-peptide levels were assayed at baseline and follow-up period. Differences between continuous variables were compared using the Mann–Whitney U test; and categorical variables were analyzed by the chi-square test. Correlation between parameters and 30-minute postprandial C-peptide were determined by Spearman correlation test. The relationship between C-peptide and DR progression was evaluated by multivariable binary logistic regression. Two-tailed P-values

Abstract Background Persistence of β cell-function in Type 1 diabetes (T1D) is associated with glycaemia stability and lower prevalence of microvascular complications. We aimed to assess the prevalence of residual C- peptide secretion in long-term Brazilian childhood onset T1D receiving usual diabetes care and its association to clinical, metabolic variables and microvascular complications. Methods A cross-sectional observational study with 138 T1D adults with ≥ 3 years from the diagnosis by routine diabetes care. Clinical, metabolic variables and microvascular complications were compared between positive ultra-sensitive fasting serum C-peptide (FCP +) and negative (FCP-) participants. Results T1D studied had ≥ 3 yrs. of diagnosis and 60% had FCP > 1.15 pmol/L. FCP + T1D were older at diagnosis (10 vs 8 y.o; p = 0.03) and had less duration of diabetes (11 vs 15 y.o; p = 0.002). There was no association between the FCP + and other clinical and metabolic variable but there was inversely association with microalbuminuria (28.6% vs 13.4%, p = 0.03), regardless of HbA1c. FCP > 47 pmol/L were associated with nephropathy protection but were not related to others microvascular complications. Conclusion Residual insulin secretion is present in 60% of T1D with ≥ 3 years of diagnosis in routine diabetes care. FCP + was positively associated with age of diagnosis and negatively with duration of disease and microalbuminuria, regardless of HbA1c.

Abstract Background Hyperglycemic memory (HGM) is a pivotal phenomenon in the development of diabetic complications. Although coincident diabetic complications are reported, research on their development and treatment is limited. Thus, we investigated whether C-peptide can simultaneously inhibit HGM-induced retinal, pulmonary, and glomerular dysfunctions in diabetic mice supplemented with insulin. Methods Insulin-treated diabetic mice were supplemented with human C-peptide by subcutaneous implantation of K9-C-peptide depots for 4 weeks, and reactive oxygen species (ROS) generation, transglutaminase (TGase) activity, and vascular leakage were examined in the retina, lung, and kidney. Results We found hyperglycemia-induced persistent ROS generation and TGase activation after blood glucose normalization in the retina, lung, and kidney of insulin-supplemented diabetic mice. These pathological events were inhibited by systemic supplementation of human C-peptide via subcutaneous implantation of a thermosensitive biopolymer-conjugated C-peptide depot. ROS generation and TGase activation were in a vicious cycle after glucose normalization, and C-peptide suppressed the vicious cycle and subsequent endothelial permeability in human retinal endothelial cells. Moreover, C-peptide supplementation ameliorated HGM-induced retinal vascular leakage and neurodegeneration, pulmonary vascular leakage and fibrosis, and glomerular adherens junction disruption and vascular leakage. Conclusions Overall, our findings demonstrate that C-peptide supplementation simultaneously attenuates vascular and neuronal dysfunctions in the retina, lung, and glomerulus of insulin-supplemented diabetic mice.

Abstract Background Type 1 diabetes mellitus (T1DM) is a common chronic systemic disease that threatens the health of children worldwide. Diabetic ketoacidosis (DKA) is the most severe acute complication of diabetes and can lead to death. This study aimed to explore the epidemiological features, clinical manifestations, and risk factors for DKA in children and adolescents newly diagnosed with T1DM in the Department of Endocrinology of the Children’s Hospital of Henan Province. Methods Medical records of 683 children and adolescents newly diagnosed with T1DM in our center from March 2014 to November 2021 were retrospectively analyzed. The data included the general condition, laboratory indexes, and clinical symptoms. The patients were divided into three groups according to age: Group I, 0–3 years; Group II, 4–9 years; and Group III, 10–18 years. Results The incidence of DKA was 62.96% and was highest in Group I. Group I had the lowest C-peptide and hemoglobin A1c, but the highest blood glucose at first diagnosis, and 25-hydroxyvitamin D3 levels, hospitalization lengths, and medical costs. 25.5% of the children were delayed in diagnosis. Logistic regression analysis showed that elevated HbA1c levels and hyperglycemia were independent risk factors for DKA. On the other hand, C-peptide and 25- hydroxyvitamin D were protective factors for DKA. Conclusions The incidence of DKA among children and adolescents in the Henan Province is very high. Moreover, DKA can be easily delayed in diagnosis. Newly diagnosed infants with T1DM are more likely to present with DKA, suffer more severe metabolic disorders, endure longer hospital stays, and accrue higher medical costs.

In clinical practice, the distinction between type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) can be challenging, leaving patients with “ambiguous” diabetes type. Insulin-treated patients (n=115) previously diagnosed with T2DM had to be re-classified based on clinical phenotype and laboratory results, and were operationally defined as having an ambiguous diabetes type. They were compared against patients with definite T1DM and T2DM regarding 12 clinical and laboratory features typically different between diabetes types. Characteristics of patients with ambiguous diabetes type, representing approximately 6% of all patients with T1DM or T2DM seen at our specialized clinic, fell in between those of patients with definite T1DM and T2DM, both regarding individual features and with respect to a novel classification based on multi-variable regression analysis (P

Meta-analysis studying the role of verapamil in improving C-peptide in people with recent-onset type-1 diabetes (T1DM) has not been conducted to date. We undertook this meta-analysis to address this knowledge gap. Electronic databases were systematically reviewed for RCTs having individuals with T1DM receiving verapamil in the treatment arm and placebo in the control arm over the standard of care. The primary outcome was to evaluate changes in the C-peptide area under the curve (AUC) at a one-year follow-up. Secondary outcomes were to assess alterations in C-peptide AUC, glycated hemoglobin (HbA1c), blood pressure, heart rate, and side effects at different time intervals over a one-year follow-up. From the initially screened 27 articles, data from two RCTs (112 patients) satisfied the inclusion criteria and were analyzed. Compared to placebo, C-peptide AUC in individuals receiving verapamil was not different at three months [MD 0.17 nmol/L (95%CI: -0.05-0.38); P = 0.13; I2 = 86%] but significantly higher at 1-year [MD 0.27 nmol/L (95%CI: 0.19–0.35); P < 0.01; I2 = 12%]. The verapamil arm showed similar changes in HbA1C at three months [MD 0.23% (95%CI: -0.43–0.90); P = 0.49; I2 = 88%] and 1-year [MD 0.18% (95% CI: -0.74 – 1.10); P = 0.70; I2 = 89%] compared to placebo. Occurrence of treatment-emergent adverse events [Risk ratio (RR) 1.90 (95%CI: 0.52–6.91); P = 0.33; I2 = 63%], serious adverse events [RR 1.40 (95%CI: 0.50–3.93); P = 0.53], constipation [RR4.11 (95%CI: 0.93–18.13); P = 0.06; I2 = 0%], headache [RR0.48 (95%CI: 0.16–1.43); P = 0.19; I2 = 0%], severe hypoglycemia [RR 0.87 (95%CI: 0.06 – 13.51); P = 0.92] were comparable across groups. Verapamil was well tolerated, and its use over one year was associated with significant improvements in C-peptide AUC though the HbA1c remained unchanged.

AbstractType 2 diabetes (T2DM) is a common comorbidity in COVID-19 patients, which could favor disease progression. Our study aimed to evaluate the impact of some glycemic biomarkers on characteristic features of COVID-19. Electronic medical records of patients consecutively admitted to a COVID-19 ward were analyzed. Demographic and anthropometric as well as clinical and laboratory parameters were obtained. T2DM was present in 47% of the patients, with 22.58% of diabetic patients being newly diagnosed at admission. The most important predictors of severe COVID-19 were age (OR 1.214 [1.078-1.366], p = 0.001), creatinine levels (OR 1.018 [1.003-1.034], p = 0.017), glucose above 7.0 mmol/L at admission (OR 7.800 [2.232-27.255], p = 0.001) and HbA1c ≥ 6.5% (OR 4.840 [1.428-16.405], p = 0.011) irrespective of the presence of DM. C-peptide levels correlated positively with age, creatinine level, the severity of hypoxia and ferritin levels of patients (p

Worldwide, diabetes and its complications have seriously affected people’s quality of life and become a serious public health problem. C-peptide is not only an indicator of pancreatic β-cell function, but also a biologically active peptide that can bind to cell membrane surface signaling molecules and activate downstream signaling pathways to play antioxidant, anti-apoptotic and inflammatory roles, or regulate cellular transcription through internalization. It is complex how C-peptide is related to diabetic complications. Both deficiencies and overproduction can lead to complications, but their mechanisms of action may be different. C-peptide replacement therapy has shown beneficial effects on diabetic complications in animal models when C-peptide is deficient, but results from clinical trials have been unsatisfactory. The complex pattern of the relationship between C-peptide and diabetic chronic complications has not yet been fully understood. Future basic and clinical studies of C-peptide replacement therapies will need to focus on baseline levels of C-peptide in addition to more attention also needs to be paid to post-treatment C-peptide levels to explore the optimal range of fasting C-peptide and postprandial C-peptide maintenance.

Abstract Background and Aims Cardiovascular diseases (CVDs) are among the leading causes of disability and early death in sub‐Saharan Africa. Most of the current blood tests for CVD diagnosis involve performing about three test profiles; often at additional cost to patients. C‐peptide, a cleavage product of proinsulin, is a promising marker that has the potential to serve as a proxy marker for diagnosing CVDs in resource‐poor settings. Methodology The study was an observational cross‐sectional one and involved 127 consenting persons diagnosed with CVD and 127 individuals without CVD. The socio‐demographic and clinical characteristics of participants were obtained. Blood levels of C‐peptide, fasting plasma glucose (FPG), total creatinine kinase (CK), creatine kinase myocardial bound (CKMB), lactate dehydrogenase (LDH), propeptide of brain natriuretic peptide (PBNP), Troponin T, lipids, and biomarkers of kidney and liver function were analyzed using ELISA and an automated analyzer. Insulin resistance was computed using the modified homeostatic model assessment (HOMA‐IR). Results The CVD Group had significantly higher levels of C‐peptide, CK, CKMB, troponin T, PBNP, FPG, HOMA‐IR, and several selected kidney, liver, and lipid parameters compared to the non‐CVD Group (p

The definition of Insulin autoimmune syndrome includes the presence of high levels of blood insulin and insulin autoantibodies. We encountered a 45-years-old white man with a high insulin serum value that do not fit with the C-peptide result. To discard or to confirm an analytical interference and diagnose a possible Insulin Autoimmune Syndrome we performed the following investigations: dilution linearity test, heterophilic antibody blocking, polyethylene glycol precipitation, measurements with alternative assays, and gel filtration chromatography by size exclusion. The latter technique confirmed that most of the insulin was complexed with a 150-kDa protein, corresponding to immunoglobulin G, identified as insulin autoantibodies. These antibodies were responsible for hypoglycemia attacks in the patient, who had a previous autoimmune disease. This case highlights the importance of carefully analyzing the results and ruling out possible interferences, as well as considering all kinds of pathologies, even if they are infrequent.

Background: The prevalence of obesity has increased in patients with type 1 diabetes (T1D) and latent autoimmune diabetes of the adult (LADA), limiting the use of clinical features such as the body mass index for its differentiation with type 2 diabetes (T2D). Additionally, some patients with maturity-onset diabetes of the young (MODY) or LADA are misdiagnosed as having T2D. The evaluation of autoantibodies and genetic testing are not fully available. We aimed to evaluate the utility of a widely available and less expensive diagnostic tool such as C-peptide to differentiate between T1D, T2D, MODY, and LADA. Methods: Our study included 38 patients with T1D, 49 with T2D, 13 with MODY, and 61 with LADA. We recorded anthropometric measurements, biochemical profiles, and antidiabetic treatment and determined C-peptide, anti-GAD65, and anti-IA2 antibodies. Results: C-peptide concentration differed significantly among populations (T1D: 0.2 ng/mL; T2D: 2.4 ng/mL; MODY: 1.14 ng/mL; LADA: 1.87 ng/mL). Through a ROC curve, we observed that the C-peptide cut-off point of 0.95 ng/mL allows differentiation between T1D and T2D (sensitivity 82%, specificity 77%); 0.82 ng/mL between T1D and LADA (sensitivity 82%, specificity 77%); and 1.65 ng/mL between T2D and MODY (sensitivity 72%, specificity 72%). Conclusions: C-peptide is useful for the diagnostic differentiation of patients with type 1, type 2 diabetes, MODY, and LADA.

Context: Type 1 diabetes (T1D) results from the autoimmune T-cell mediated destruction of pancreatic beta cells leading to insufficient insulin secretion. At the time of diagnosis of T1D, there is residual beta cell function that declines over the subsequent months to years. Recent interventions have been approved to preserve beta cell function in evolving T1D. Objective: The aim of this review is to summarise the approaches used to assess residual beta cell function in evolving T1D, and to highlight potential future directions. Methods: Studies including subjects aged 0 to 18 years were included in this review. The following search terms were used; “(type 1 diabetes) and (partial remission)” and “(type 1 diabetes) and (honeymoon)”. References of included studies were reviewed to determine if additional relevant studies were eligible. Results: There are numerous approaches to quantifying beta cell reserve in evolving T1D. These include c-peptide measurement after a mixed meal or glucagon stimuli, fasting c-peptide, the urinary c-peptide/creatinine ratio, insulin dose-adjusted haemoglobin A1c, and other clinical models to estimate beta cell function. Other biomarkers may have a role, including the proinsulin/c-peptide ratio, cytokines, and microRNA. Studies using thresholds to determine if residual beta cell function is present often differ in values used to define remission. Conclusions: As interventions are approved to preserve beta cell function, it will become increasingly necessary to quantify residual beta cell function in research and clinical contexts. In this report, we have highlighted the strengths and limitations of the current approaches.

Abstract Aims/Introduction This study aimed to identify the clinical factors affecting postoperative residual pancreatic β‐cell function, as assessed by the C‐peptide index (CPI), and to investigate the association between perioperative CPI and the status of diabetes management after pancreatectomy. Materials and Methods The associations between perioperative CPI and clinical background, including surgical procedures of pancreatectomy, were analyzed in 47 patients who underwent pancreatectomy, and were assessed for pre‐and postoperative CPI. The association between perioperative CPI and glycemic control after pancreatectomy was investigated. Results The low postoperative CPI group (CPI