Diabetic neuropathy in children and adolescents with type 1 diabetes mellitus: Diagnosis, pathogenesis, and associated genetic markers

Risk Factors for Subclinical Diabetic Peripheral Neuropathy in Type 2 Diabetes Mellitus

Purpose

To investigate the risk factors associated with subclinical diabetic peripheral neuropathy (sDPN) in patients with type 2 diabetes mellitus (T2DM).

Patients and Methods

This cross-sectional, retrospective study involved 311 patients with T2DM who were successively admitted from January 2018 to December 2021 without any neurological symptoms. All participants underwent a nerve conduction study (NCS), and those asymptomatic patients with abnormal nerve conduction were diagnosed with sDPN. Differences between groups were evaluated by the chi-squared, Wilcoxon, or Fisher's exact test. Binary logistic regression analysis was performed to determine the independent risk factors for sDPN. Receiver operating characteristic (ROC) curves were constructed, and the areas under curves (AUCs) were detected.

Results

Among 311 asymptomatic patients with T2DM, 142 (45.7%) with abnormal nerve conduction were diagnosed with sDPN. Patients with sDPN significantly differed from those without diabetic peripheral neuropathy (DPN) in age, history of hypertension, duration of diabetes, anemia, neutrophil-to-lymphocyte ratio, fasting C-peptide level, serum creatinine level, and albuminuria (all p<0.05). Furthermore, the duration of diabetes (odds ratio [OR]: 1.062, 95% confidence interval [CI]: 1.016-1.110), fasting C-peptide level (OR: 2.427, 95% CI: 1.126-5.231), and presence of albuminuria (OR: 2.481, 95% CI: 1.406-4.380) were independently associated with the development of sDPN (all p<0.05). The AUCs for fasting C-peptide level, duration of diabetes, and the two factors combined were 0.6229 (95% CI: 0.5603-0.6855, p=0.0002), 0.6738 (95% CI: 0.6142-0.7333, p<0.0001), and 0.6808 (95% CI: 0.6212-0.7404, p<0.0001), respectively.

Conclusion

For patients with T2DM and longer duration of diabetes, lower fasting C-peptide levels, and presence with albuminuria, the risk for developing DPN is higher even if they have no clinical signs or symptoms. Identifying potential risk factors for the development of sDPN and effectively controlling them early are critical for the successful management of DPN.

Observation of the neuroprotective efficacy of vitamin K in a streptozocin-induced diabetes model in chick embryos

Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia due to insulin deficiency and/or resistance. Vitamin K (VK) is a group of fat-soluble molecules, including naturally occurring vitamin K1 (phylloquinone). vitamin K2 (menaquinone), and synthetic vitamin K3 (menadione). Beyond coagulation, the health benefits of VK have been described to play different roles in both physiological and pathological processes such as inflammation, energy metabolism, neuroprotection, cellular growth, and survival. It was aimed to observe the antioxidant and/or neuroprotective activity of vitamin K1 in our model of chick embryo diabetic neuropathy (DN) induced by streptozotocin (STZ). Ninety White Leghorn, fertile and 0-day-old SPF (specific pathogen-free) eggs (57 ± 4 gr) were used in the study. Chick embryo blood brain tissues were taken for biochemical evaluation. Plasma insulin and glucose levels were measured. In addition, brain tissue total antioxidant level (TAS), total oxidant level (TOS), malondialdehyde (MDA), and vascular endothelial growth factor (VEGF) levels were measured. Plasma glucose levels were higher in the STZ-treated groups and lower in the treatment groups. Plasma insulin levels were observed to be higher in STZ groups in groups treated with high VK. Low TAS, high MDA, TOS, and VEGF levels were recorded in brain tissue STZ groups. Low VEGF, TOS, and MDA levels were recorded in the group treated with the highest VK, while high TAS levels were observed. In our STZ-induced chick embryo diabetic neuropathy model, we observed that VK1 reduced oxidant damage by showing antioxidant properties or by modulating antioxidant enzymes.

Slowing of Peripheral Nerve Conduction Velocity in Children and Adolescents With Type 1 Diabetes Is Predicted by Glucose Fluctuations

Nerve conduction velocity (NCV) abnormalities are the forerunners of diabetic peripheral neuropathy (DPN). Therefore, this study aimed to analyze the effect of glucose profile quality on NCV in children and young adults with type 1 diabetes. Fifty-three children age 5 to 23 years with type 1 diabetes were recruited to participate in the study, which was conducted prospectively at the Children's Hospital of Eastern Switzerland from 2016 to 2022. Glycemic targets were recorded, and a cross-sectional nerve conduction study analyzing the peroneal, tibial, median motor, and median sensory nerves was performed. Data were compared with those of a control group of 50 healthy children. In the age- and height-matched diabetes subgroup aged 10-16 years, all four nerves showed significantly slower NCV, most pronounced for the peroneal nerve. Because height has a retarding effect on peroneal NCV, NCV was adjusted for height (dNCV). Peroneal dNCV correlated negatively with long-term glycated hemoglobin and highly significantly with glucose variability. Because high glucose variability clearly increases the risk of neuropathy, together with but also independently of the mean glucose level, this aspect of glycemic control should be given more attention in the care of individuals with diabetes.

ARTICLE HIGHLIGHTS

There is a strong need for the better identification of early subclinical manifestations of microvascular complications, such as diabetic peripheral neuropathy, in young individuals with diabetes. To identify peripheral neuropathy and contributing factors at an asymptomatic disease stage, and to exclude height as a known modifying factor, we performed association studies of height-adjusted nerve conduction velocity. We identified high glucose variability, especially the SD of mean glucose, as an unexpectedly strong predictor of slowed nerve conduction velocity. More attention should be paid to the goal of low glucose variability in the care of individuals with diabetes.

Neuropathy in paediatric type 1 diabetes mellitus - clinical characterization and analysis of risk factors in the diabetes prospective follow-up registry DPV (Diabetes-Patienten-Verlaufsdokumentation)-registry

OBJECTIVES

Data on the prevalence, clinical features and risk factors associated with paediatric diabetic neuropathy (DN) are scarce.

METHODS

We retrospectively analysed data from the DPV registry, including patients under 20 years of age, treated for type 1 diabetes mellitus (T1D) between 2005 and 2021. Patients with non-diabetic neuropathy were excluded. Data came from centres in Austria, Germany, Luxembourg and Switzerland.

RESULTS

1,121 of the 84,390 patients included had been diagnosed with DN. Univariate analysis showed patients with DN to be older and predominantly female, with a longer duration of T1D, higher insulin dosages per kg and day, lower rates of insulin pump therapy, higher postprandial glucose-, higher HbA_1c-and higher cholesterol levels, and higher diastolic and systolic blood pressure values. There was also a larger proportion of smokers and higher prevalence of diabetic retinopathy. Median duration of diabetes at diagnosis of DN was 8.3 years. Multivariable analysis, adjusted for demographics revealed an increased risk for DN among female patients and those who were older, underweight (BMI-SDS), smoked cigarettes or had a longer duration of T1D or higher levels of HbA_1c and postprandial blood glucose. The presence of retinopathy and higher cholesterol levels were also linked to increased risk while not-using insulin pump therapy was not.

CONCLUSIONS

DN can develop after just a short duration of T1D. Prevention may be achieved by a lowering of HbA_1c-and postprandial glucose levels through improved glycaemic control. This warrants further investigation. The slight female predominance suggests further hormonal and genetic etiological factors.

Biomarkers in diabetic neuropathy

CONTEXT

The prevalence of diabetic neuropathy is drastically increasing in the world. To halt the progression of diabetic neuropathy, there is an unmet need to have potential biomarkers for the diagnosis and new drug discovery.

OBJECTIVE

To study various biomarkers involved in the pathogenesis of diabetic neuropathy.

METHODS

The literature was searched with the help of various scientific databases and resources like PubMed, ProQuest, Scopus, and Google scholar from the year 1976 to 2020.

RESULTS

Biomarkers of diabetic neuropathy are categorised as inflammatory biomarkers such as MCP-1, VEGF, TRPV1, NF-κB; oxidative biomarkers such as adiponectin, NFE2L2; enzyme biomarkers like NADPH, ceruloplasmin, HO-1, DPP-4, PARP α; miscellaneous biomarkers such as SIRT1, caveolin 1, MALAT1, and microRNA. All biomarkers have a significant role in the pathogenesis of diabetic neuropathy.

CONCLUSION

These biomarkers have a potential role in the progression of diabetic neuropathy and can be considered as potential targets for new drug discovery.

Corneal nerve and nerve conduction abnormalities in children with type 1 diabetes

OBJECTIVE

In vivo corneal confocal microscopy (CCM) is a novel, rapid, and non-invasive technique that identifies early small fiber damage and can predict the progression and development of clinical neuropathy in adults with type 1 diabetes. However, its usefulness in children is not well established. This study compared corneal confocal microscopy with neuropathic symptoms, signs, and objective measures of neuropathy for the diagnosis of diabetic neuropathy in children with type 1 diabetes.

RESEARCH DESIGN AND METHODS

A total of 83 children with type 1 diabetes and 83 healthy participants of similar age underwent assessment of neuropathy symptoms, signs, nerve conduction studies, quantitative sensory and autonomic function testing, and in vivo CCM.

RESULTS

Only of 3/83 (4%) children with type 1 diabetes had subclinical neuropathy. However, corneal nerve fiber density (p = 0.001), branch density (p = 0.006), fiber length (p = 0.002), tibial motor nerve amplitude and conduction velocity, and sural sensory nerve amplitude and conduction velocity (all p < 0.004) were lower in participants with type 1 diabetes than in the controls. Vibration, cooling, and warm perception thresholds and deep breathing heart rate variability were not found to be different (all p > 0.05) between children with type 1 diabetes and healthy controls. Multivariate regression analysis identified a possible association between body mass index and decreased corneal nerves.

CONCLUSIONS

Decreased corneal nerves and abnormal nerve conduction were found in children with type 1 diabetes. CCM may allow rapid objective detection of subclinical diabetic neuropathy in children and adolescents with type 1 diabetes.

Impairment of insulin signaling pathway PI3K/Akt/mTOR and insulin resistance induced AGEs on diabetes mellitus and neurodegenerative diseases: a perspective review

Insulin resistance is common in type 2 diabetes mellitus (T2DM), neurodegenerative diseases, cardiovascular diseases, kidney diseases, and polycystic ovary syndrome. Impairment in insulin signaling pathways, such as the PI3K/Akt/mTOR pathway, would lead to insulin resistance. It might induce the synthesis and deposition of advanced glycation end products (AGEs), reactive oxygen species, and reactive nitrogen species, resulting in stress, protein misfolding, protein accumulation, mitochondrial dysfunction, reticulum function, and metabolic syndrome dysregulation, inflammation, and apoptosis. It plays a huge role in various neurodegenerative diseases like Parkinson's disease, Alzheimer's disease, Huntington's disease, and Amyloid lateral sclerosis. In this review, we intend to focus on the possible effect of insulin resistance in the progression of neurodegeneration via the impaired P13K/Akt/mTOR signaling pathway, AGEs, and receptors for AGEs.

Investigation of Natural Compounds for Therapeutic Potential in Streptozotocin-induced Diabetic Neuroinflammation and Neuropathic Pain

Diabetic neuropathy (DN) is a serious microvascular complication of diabetes mellitus (DM) that impacts the nervous system. Several risk factors are involved in the progression and maintenance of DN-associated pain, such as higher expression of various inflammatory mediators, e.g., tumor necrotic factor-alpha (TNF-α), nuclear factor-kappa B (NF-κB), and cyclo-oxygenase-2 (COX-2). The present research explores the neuroprotective potential of natural isolates, including berbamine, bergapten, and carveol, on the DM-induced neuroinflammation and neurodegeneration that cause neuropathic pain. The study utilized computerized techniques, including computational analysis (a docking assay and a molecular dynamic simulation) before moving to in vivo protocols. Diabetic neuropathy was induced by intraperitonial injection (IP) of streptozotocin (65 mg/kg), and the animal subjects (rats) were kept for 4 weeks for the development of DN. Once diabetic neuropathy was confirmed, the subjects were treated with berbamine, bergapten, and carveol until the sixth week (i.e., 2 weeks of treatment). At the sixth week, the rats were sacrificed, and the sciatic nerve and spinal cord of each was collected for further molecular investigation. Docking and a molecular dynamic simulation (MDS) delivered the information that the natural compounds (berbamine, bergapten, and carveol) were interacting with the selected target protein (i.e., mitogen-activated protein kinase). After IP, it was found that berbamine, bergapten, and carveol had ameliorated mechanical allodynia and thermal hyperalgesia by the 28th day of the study (2 weeks after treatment) without affecting blood glucose levels. Berbamine, bergapten, and carveol markedly elevated the levels of glutathione (GSH) and glutathione s-transferase (GST), in both the sciatic nerve and spinal cord, and also reduced lipid peroxidase (LPO) and nitric oxide (NO). The abovementioned natural isolates reduced pathologic alterations provoked through DN, a finding confirmed through histopathological assays (hematoxylin and eosin staining and immuno-histochemical analysis). Treatment down regulated higher expressions of the inflammatory mediatorcyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and nuclear factor kappa B (NF-κB), as confirmed by ELISA and polymerase chain reaction (PCR). The outcomes of berbamine, bergapten, and carveol are compared with those of pregabalin as a positive control group. Compared to pregabalin, treatment with the aforementioned three natural compounds improved nociception and reduced hyperalgesic effects, and consequently reduced pain perception and inflammation. Our results suggest the mechanism for the neuro-protective impact of berbamine, bergapten, and carveol might possibly be arbitrated via COX-2, TNF-α, and NF-κB, and regulated by mitogen-activated protein kinase, ultimately ameliorating STZ-provoked, DM-induced neuroinflammation and neurodegeneration, and associated neuropathic pain.

Subclinical Neuropathy in Children With Type I Diabetes Mellitus: Tertiary Care Centre Experience

Introduction: Diabetic peripheral neuropathy is a common complication of diabetes mellitus (DM) type 1. However, it can occur without evidence of symptoms or clinical signs of neuropathy labeled as subclinical neuropathy, which neurophysiological studies can best detect.

Purpose: To evaluate the prevalence of subclinical neuropathy among children with DM type 1, determine the association with blood sugar control, and evaluate the pattern of nerve involvement in neurophysiological studies.

Methods: This cross-sectional study evaluated 100 children with DM type 1, aged five to 15 years, at least one year after the diagnosis. Subclinical neuropathy was evaluated using nerve conduction study. Glycemic control was assessed using hemoglobin A1c (HbA1c).

Results: The mean age of subjects was 11.5 ± 0.25 years. The average age at the onset of the disease was 5.95 ± 0.25 years. There were 64 patients who had electrophysiological evidence of peripheral neuropathy. The most observed electrophysiological changes were distal latency abnormalities in the left and right peroneal nerves in 39 and 33 patients, respectively. Sensory nerve amplitude, peak latency, and conduction velocity were normal in all patients (100%). HbA1c level did not show a statistically significant association with the incidence of subclinical neuropathy.

Conclusion: Subclinical neuropathy was prevalent in children with DM type 1. Poor glucose control was only associated with an increased odds ratio of subclinical neuropathy.

Prevalence of peripheral neuropathy and associated risk factors in children with type 1 diabetes

AIM

To detect the prevalence of diabetic polyneuropathy (DPN) in children with type 1 diabetes (T1D) and to identify associated the risk factors.

METHODS

This cross-sectional study evaluated children aged between 2 and 16y with T1D for ≥2 y. Detailed neurological examination, neuropathy symptom score, and nerve conduction studies were done in all children to assess nerve dysfunction. Disease-related factors were evaluated for the prediction of neuropathy.

RESULTS

Sixty-six children (67% boys) were enrolled. The mean age at the time of diagnosis of T1D was 7.1 ± 2.6 years. The mean duration of diabetes was 4 ± 1.8 years. None of the patients had neuropathy on clinical examination or on the neuropathy symptom score. The prevalence of subclinical DPN was 18.2% (n = 12/66). The type of neuropathy was pure motor (n = 11, 91.6%) and mixed sensorimotor (n = 1, 8.3%). The common peroneal nerve was most commonly affected (n = 6, 50%), followed by the tibial (n = 4, 33.3%) nerve. The most common patterns of nerve involvement were mixed axonal and demyelination (n = 7, 58.3%), followed by axonal (n = 3, 25%) and demyelinating type (n = 2, 16.6%). Children with subclinical DPN had a significant reduction in velocity of tibial, common peroneal, median motor, and ulnar motor nerves; delayed latency in common peroneal, median motor, ulnar motor, and median sensory nerves compared to those without DPN (p value <0.05). A higher body mass index predicted the development of subclinical DPN (p value <0.05).

CONCLUSION

Nearly one-fifth of children with T1D have subclinical neuropathy as early as two years of the disease. A higher body mass index is significantly associated with DPN. Electrophysiological studies should be performed regularly to screen for nerve dysfunction and its progression.

Homozygosity of the Z-2 polymorphic variant in the aldose reductase gene promoter confers increased risk for neuropathy in children and adolescents with Type 1 diabetes

BACKGROUND

Diabetic neuropathy (DN) is the least recognized complication of diabetes mellitus and may start early in the course of the disease. Aldose reductase (AKR1B1) gene promoter Z-2/Z-2 polymorphism increases the expression of AKR1B1 enzyme and may contribute to DN.

SUBJECTS

We evaluated 108 Type 1 diabetes (T1D) children and adolescents (mean ± SD age: 13.5 ± 3.46 years, disease duration: 5.3 ± 3.4 years) and 150 healthy controls (age: 11.9 ± 2.7 years).

METHODS

In both groups, pupillary dilation (PD) in darkness, postural blood pressure test (PBPT), and vibration sensation thresholds (VST) in upper and lower limbs were estimated as indices of autonomic and peripheral neuropathy, respectively. Nerve conduction studies (NCS) were performed in patients as peripheral neuropathy index. The polymorphisms of AKR1B1 gene were evaluated using microsatellite (AC)n sequence Z.

RESULTS

PBPT, PD, and VST impairments were more frequent in patient group compared with controls, while 38.6% of patients exhibited NCS abnormality. Gender, age, pubertal status, height, body mass index, diabetes duration, HbA1c, and anti-GAD titers were associated with neuropathy indices in patients. There was a strong correlation between PD and NCS in patients, while homozygous patients for Z-2 AKR1B1 gene polymorphism had higher prevalence of abnormal NCS (83.3% vs. 34.6%), PD (62.5% vs. 31.5%), and PBPT values compared with heterozygous or negative patients. Homozygous AKR1B1 status predicted PD, NCS, and PBPT variance, while PD, VST, NCS, and PBPT parameters accurately discriminated homozygous AKR1B1 patients.

CONCLUSIONS

Impaired indices of peripheral and autonomic DN were present in a significant proportion of young T1D patients. PD, VST, NCS, and PBPT parameters were simultaneously associated with homozygous state of AKR1B1 Z-2 gene polymorphism, implicating polyol metabolism with both autonomic and peripheral neuropathies.

Vibrotactile sense might improve over time in paediatric subjects with type 1 diabetes-A mid-term follow-up using multifrequency vibrometry

AIM

Impaired vibrotactile sense, mirroring diabetic peripheral neuropathy, is present among children and adolescents with type 1 diabetes. This study aims to re-examine the vibrotactile sense of paediatric type 1 diabetes subjects in order to evaluate any alterations in the vibrotactile sense over time.

METHODS

A VibroSense Meter I device was used to determine the vibrotactile perception thresholds (VPTs) for seven frequencies from the pulp of index and little fingers and for five frequencies from metatarsal heads one and five on the sole of the foot, of 37 children and adolescents with type 1 diabetes, previously examined in a larger cohort. Subjects were followed up after a median time of 30 months. Z-scores of VPTs were calculated using previously collected normative data.

RESULTS

Vibrotactile perception thresholds improved over time at low frequencies (especially 16 Hz) on the foot, while not being statistically significant different on the rest of the frequencies, either on hand or foot. VPTs were not correlated with HbA1c.

CONCLUSION

A mid-term follow-up of vibrotactile sense in paediatric subjects with type 1 diabetes shows a conceivable normalization of previously impaired vibrotactile sense on some frequencies on the foot, indicating that vibrotactile sense might fluctuate over time.

Emerging Role of Epitranscriptomics in Diabetes Mellitus and Its Complications

Diabetes mellitus (DM) and its related complications are among the leading causes of disability and mortality worldwide. Substantial studies have explored epigenetic regulation that is involved in the modifications of DNA and proteins, but RNA modifications in diabetes are still poorly investigated. In recent years, posttranscriptional epigenetic modification of RNA (the so-called 'epitranscriptome') has emerged as an interesting field of research. Numerous modifications, mainly N⁶ -methyladenosine (m⁶A), have been identified in nearly all types of RNAs and have been demonstrated to have an indispensable effect in a variety of human diseases, such as cancer, obesity, and diabetes. Therefore, it is particularly important to understand the molecular basis of RNA modifications, which might provide a new perspective for the pathogenesis of diabetes mellitus and the discovery of new therapeutic targets. In this review, we aim to summarize the recent progress in the epitranscriptomics involved in diabetes and diabetes-related complications. We hope to provide some insights for enriching the understanding of the epitranscriptomic regulatory mechanisms of this disease as well as the development of novel therapeutic targets for future clinical benefit.

Large fibre, small fibre and autonomic neuropathy in adolescents with type 1 diabetes: A systematic review

AIMS

To estimate the prevalence of neuropathy in adolescents with type 1 diabetes.

METHODS

Systematic collection of published studies exploring the prevalence of large fibre neuropathy (LFN), small fibre neuropathy (SFN), and autonomic neuropathy in adolescents with type 1 diabetes. Following prospective registration (Prospero CRD42020206093), PubMed, EMBASE, and Cochrane Library were searched for studies from 2000 to 2020. PICO framework was used in the selection process (Population: adolescents aged 10-19 years with type 1 diabetes; Intervention: diagnostic methods for neuropathy; Comparison: reference data; Outcome: data on prevalence or comparison). Data were extracted concerning study quality based on available data and established methods for determining and diagnosing various neuropathy types.

RESULTS

From 2,017 initial citations, 27 studies (7589 participants) fulfilled eligibility criteria. The study population (47% males) had a diabetes duration between 4.0 and 10.6 years, and HbA1c level between 7.3 and 10.8%, 56-95 mmol/mol. The prevalence of LFN, based on nerve conduction studies, was 10-57%. Based on other tests for neuropathy, the prevalence of LFN and SFN was 12-62%, and that of cardiac autonomic neuropathy was 12-75%.

CONCLUSION

The described prevalence of neuropathy in adolescents with type 1 diabetes varied, which can be methodological due to different screening methods and classifications of neuropathy.

Diabetic eye: associated diseases, drugs in clinic, and role of self-assembled carriers in topical treatment

Introduction: Diabetes is a pandemic disease that causes relevant ocular pathologies. Diabetic retinopathy, macular edema, cataracts, glaucoma, or keratopathy strongly impact the quality of life of the patients. In addition to glycemic control, intense research is devoted to finding more efficient ocular drugs and improved delivery systems that can overcome eye barriers. Areas covered: The aim of this review is to revisit first the role of diabetes in the development of chronic eye diseases. Then, commercially available drugs and new candidates in clinical trials are tackled together with the pros and cons of their administration routes. Subsequent sections deal with self-assembled drug carriers suitable for eye instillation combining patient-friendly administration with high ocular bioavailability. Performance of topically administered polymeric micelles, liposomes, and niosomes for the management of diabetic eye diseases is analyzed in the light of ex vivo and in vivo results and outcomes of clinical trials. Expert opinion: Self-assembled carriers are being shown useful for efficient delivery of not only a variety of small drugs but also macromolecules (e.g. antibodies) and genes. Successful design of drug carriers may offer alternatives to intraocular injections and improve the treatment of both anterior and posterior segments diabetic eye diseases.

Protective potential of cerium oxide nanoparticles in diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) is a non-communicable metabolic disease which is closely related to excessive oxidative stress after constant exposure to high plasma glucose. Although the current antidiabetic medications are effective in lowering blood glucose, these medications do not prevent or reverse the disease progression. Thus, there is a crucial need to explore new therapeutic interventions that could address this shortcoming. As cerium oxide nanoparticles (CONPs) possess antioxidant property, this agent may be used as a treatment option for the management of DM.

PURPOSE

This review aims to provide a critical evaluation of the pharmacological and antidiabetic effects of CONPs in cell and animal models. The roles of CONPs in attenuating DM complications are also presented in this report.

METHODS

We conducted a literature search in the PubMed database using the keywords "cerium oxide", "cerous oxide", "ceria", "nanoceria", and "diabetes" from inception to December 2020. The inclusion criteria were primary source articles that investigated the role of CONPs in DM and diabetic complications.

RESULTS

We identified 47 articles from the initial search. After the thorough screening, only 31 articles were included in this study. We found that CONPs can attenuate parameters that are related to DM and diabetic complications in various animals and cell culture models.

CONCLUSION

CONPs could potentially be used in the treatment of those with DM and complications caused by the disease.

An association between fibrinogen gene polymorphisms and diabetic peripheral neuropathy in young patients with type 1 diabetes

In complex etiopathogenesis of diabetic peripheral neuropathy (DPN), hemostatic dysfunction and subclinical inflammation play a possible role. Fibrinogen is involved in both the hemostatic and inflammatory pathways, so we hypothesize that fibrinogen gene polymorphisms might be associated with DPN. A total of 127 young patients with type 1 diabetes (T1D) (average age, 18.5 ± 4.65 years; average diabetes duration, 14.5 ± 2.26 years) and 90 healthy controls were enrolled into the study. Basic biochemical and coagulation parameters were measured and gene polymorphisms of fibrinogen alpha (rs6050) and beta (rs1800790) were established. DPN was diagnosed in 38 diabetic patients by neurological examination. AA genotype and A allele of rs1800790 polymorphism of fibrinogen beta were associated with increased risk of DPN (odds ratio [OR] 4.537, 95% confidence interval [95CI] 1.14-19.94, p = 0.019 and OR 1.958, 95CI 1.038-3.675, p = 0.029, respectively). No association was found between DPN and rs6050 gene polymorphisms. Plasma fibrinogen concentration significantly correlated with HbA1c (Spearman's correlation coefficient [r] = 0.54) and HDL cholesterol (r = - 0.67). A allele and AA genotype of rs1800790 seem to be associated with DPN in young patients with T1D. Further studies are appropriate to elucidate the role of fibrinogen gene polymorphisms in the complex etiology of DPN.

Genetic and Epigenomic Modifiers of Diabetic Neuropathy

Diabetic neuropathy (DN), the most common chronic and progressive complication of diabetes mellitus (DM), strongly affects patients’ quality of life. DN could be present as peripheral, autonomous or, clinically also relevant, uremic neuropathy. The etiopathogenesis of DN is multifactorial, and genetic components play a role both in its occurrence and clinical course. A number of gene polymorphisms in candidate genes have been assessed as susceptibility factors for DN, and most of them are linked to mechanisms such as reactive oxygen species production, neurovascular impairments and modified protein glycosylation, as well as immunomodulation and inflammation. Different epigenomic mechanisms such as DNA methylation, histone modifications and non-coding RNA action have been studied in DN, which also underline the importance of “metabolic memory” in DN appearance and progression. In this review, we summarize most of the relevant data in the field of genetics and epigenomics of DN, hoping they will become significant for diagnosis, therapy and prevention of DN.

Diabetic neuropathy in children and youth: New and emerging risk factors

Pediatric neuropathy attributed to metabolic dysfunction is a well-known complication in children and youth with type 1 diabetes. Moreover, the rise of obesity and in particular of type 2 diabetes may cause an uptick in pediatric neuropathy incidence. However, despite the anticipated increase in neuropathy incidence, pathogenic insights and strategies to prevent or manage neuropathy in the setting of diabetes and obesity in children and youth remain unknown. Data from adult studies and available youth cohort studies are providing an initial understanding of potential diagnostic, management, and preventative measures in early life. This review discusses the current state of knowledge emanating from these efforts, with particular emphasis on the prevalence, clinical presentation, diagnostic approaches and considerations, and risk factors of neuropathy in type 1 and type 2 diabetes in children and youth. Also highlighted are current management strategies and recommendations for neuropathy in children and youth with diabetes. This knowledge, along with continued and sustained emphasis on identifying and eliminating modifiable risk factors, completing randomized controlled trials to assess effectiveness of strategies like weight loss and exercise, and enhancing awareness to support early detection and prevention, are pertinent to addressing the rising incidence of neuropathy associated with diabetes and obesity in children and youth.

Peripheral and Autonomic Neuropathy Status of Young Patients With Type 1 Diabetes Mellitus at the Time of Transition From Pediatric Care to Adult-Oriented Diabetes Care

INTRODUCTION

The prevalence of neuropathic lesions in young patients with type 1 diabetes mellitus (T1DM) at the time of transition from pediatric care to adult-oriented diabetes care is poorly studied. A comparative study with healthy volunteers to assess the possible neuropathic condition of this special population and to identify the potential early screening needs has not been performed yet. The results may provide important feedback to pediatric diabetes care and a remarkable baseline reference point for further follow up in adult diabetes care.

PATIENTS AND METHODS

Twenty-nine young patients with T1DM [age: 22.4 ± 2.9 years; HbA1c: 8.5 ± 2.1%, diabetes duration: 12.2 ± 5.8 years; (mean ± SD)] and 30 healthy volunteers (age: 21.5 ± 1.6 years; HbA1c: 5.3 ± 0.3%) were involved in the study. Autonomic function was assessed by standard cardiovascular reflex tests. Complex peripheral neuropathic testing was performed by Neurometer^®, Neuropad^®-test, Tiptherm^®, Monofilament^®, and Rydel-Seiffer tuning fork tests.

RESULTS

T1DM patients had significantly higher diastolic blood pressure than controls (80 ± 9 vs. 74 ± 8 mmHg, p < 0.01), but there was no significant difference in systolic blood pressure (127 ± 26 vs. 121 ± 13 mmHg). Cardiovascular reflex tests had not revealed any significant differences between the T1DM patients and controls. No significant differences with Neurometer^®, Neuropad^®-test, and Monofilament^® were detected between the two groups. The vibrational sensing on the radius on both sides was significantly impaired in the T1DM group compared to the controls with Rydel-Seiffer tuning fork test (right: 7.5 ± 1.0 vs. 7.9 ± 0.3; left: 7.5 ± 0.9 vs. 7.9 ± 0.3, p < 0.05). The Tiptherm^®-test also identified a significant impairment in T1DM patients (11 sensing failures vs. 1, p < 0.001). In addition, the neuropathic complaints were significantly more frequently present in the T1DM patient group than in the controls (9 vs. 0, p < 0.01).

CONCLUSION

In this young T1DM population, cardiovascular autonomic neuropathy and cardiac morphological alterations could not be found. However, Rydel-Seiffer tuning fork and Tiptherm^®-tests revealed peripheral sensory neurological impairments in young T1DM patients at the time of their transition to adult diabetes care.

Association of plasminogen activator inhibitor-1 4G5G Polymorphism with risk of diabetic nephropathy and retinopathy: a systematic review and meta-analysis

Background

The 4G5G polymorphism of Plasminogen activator inhibitor-1 (PAI-1) gene is reported to be associated with diabetes nephropathy and retinopathy (DNR) risk. However, the findings are conflicting. Herein, we conducted a case-control and meta-analysis study to explore the association of PAI-1 4G5G polymorphism with risk of DNR.

Methods

We retrieved PubMed, EMBASE, Web of Knowledge, and CNKI databases and screened eligible studies up to August 15, 2020. The strength of associations was assessed by odd ratio (OR) and the corresponding 95% confidence interval (95% CI).

Results

A total of 27 case-control studies including 16 studies with 1,825 cases case and 1,731 controls on DN and eleven studies with 1,397 cases and 1,545 controls on DR were selected. Pooled data showed that the PAI-1 4G5G polymorphism was significantly associated with DN (allele model: OR = 0.674, 95% CI 0.524-0.865, p = 0.002; homozygote model: OR = 0.536, 95% CI 0.351-0.817, p = 0.004; heterozygote model: OR = 0.621, 95% CI 0.427-0.903, p = 0.013; dominant model: OR = 0.575, 95% CI 0.399-0.831, p = 0.003; and recessive model: OR = 0.711, 95% CI 0.515-0.981, p = 0.038) and DR (homozygote model: OR = 0.770, 95% CI 0.621-0.955, p = 0.0.017) risk. Stratified analyses by ethnicity indicated that PAI-1 4G5G polymorphism was associated with DN and DR risk in Asians and Caucasians, respectively.

Conclusions

The present meta-analysis revealed that the PAI-1 4G5G polymorphism was associated with increased risk of DN and DR risk. However, well-designed large-scale clinical studies are required to further validate our results.

Humanoid robot-assisted interventions among children with diabetes: A systematic scoping review

BACKGROUND

Although the humanoid robot is highly engaging for children, whether humanoid robot-assisted interventions could help in diabetes management is still unclear.

OBJECTIVES

This review aimed to elucidate the roles of humanoid robot in managing diabetes and observe the effects of humanoid robot-assisted interventions among children with type I diabetes mellitus.

METHODS

Arksey and O'Malley's methodological framework was used to conduct this scoping review.

DATA RESOURCE

We conducted a comprehensive search in 10 databases, including IEEE Xplore Digital Library, CINAHL, Cochrane Library, EMBASE, PubMed, Scopus, Web of Science, ProQuest, WanFang, and CNKI, from May 1, 1989 to February 1, 2020. The reference lists of key texts were examined and citation chaining was conducted. In addition, our team searched gray literature and relevant journals to maximise the searching.

REVIEW METHODS

Two independent reviewers examined all full articles for fitness with the eligibility criteria. Items of data extraction included the characteristics of articles, description of intervention, and mechanism of humanoid robot in improving the management of children with diabetes.

RESULTS

A total of 2,755 articles were retrieved, 22 of which were included from five countries across different ethnicities. Five roles of humanoid robots in managing diabetes among children with type I diabetes mellitus were identified: disease manager, educator, advocator, emotional supporter, and communicator. To some extent, effects seem to be related to the positive improvement of affective, experiential, relational, cognitive, and behavioral perspectives from humanoid robot-assisted intervention.

CONCLUSIONS

The roles of humanoids have been designed to perform their multidomain functionality. Although many positive effects were observed, the majority of selected articles have methodological issues. Future studies need an improved methodology for large-scale controlled trials.

Diabetic neuropathy: A focus on small fibres

Diabetic peripheral neuropathy (DPN) is diagnosed too late, which contrasts with our approach for diabetic retinopathy and nephropathy, where incipient disease is detected early enabling timely treatment. The 10-g monofilament and a foot exam are the commonly used methods for screening diabetic neuropathy, but this primarily identifies moderate to severe diabetic neuropathy. Small fibres are damaged early and are associated with the development of painful diabetic neuropathy, foot ulceration, and Charcot foot. Tests of small fibre damage include thermal thresholds, microneurography, evoked potentials, sudomotor function, laser Doppler flare, skin biopsy, and corneal confocal microscopy. Measures of small fibre damage and repair may be key to the assessment of efficacy in clinical trials of disease modifying therapies for diabetic neuropathy.

Uncovering the Mechanism of Astragalus membranaceus in the Treatment of Diabetic Nephropathy Based on Network Pharmacology

BACKGROUND

Diabetic nephropathy (DN), characterized by hyperglycemia, hypertension, proteinuria, and edema, is a unique microvascular complication of diabetes. Traditional Chinese medicine (TCM) Astragalus membranaceus (AM) has been widely used for DN in China while the pharmacological mechanisms are still unclear. This work is aimed at undertaking a network pharmacology analysis to reveal the mechanism of the effects of AM in DN. Materials and Methods. In this study, chemical constituents of AM were obtained via Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), and the potential targets of AM were identified using the Therapeutic Target Database (TTD). DisGeNET and GeneCards databases were used to collect DN-related target genes. DN-AM common target protein interaction network was established by using the STRING database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were carried out to further explore the DN mechanism and therapeutic effect of AM. The network diagrams of the active component-action target and protein-protein interaction (PPI) networks were constructed using Cytoscape software.

RESULTS

A total of 16 active ingredients contained and 78 putative identified target genes were screened from AM, of which 42 overlapped with the targets of DN and were considered potential therapeutic targets. The analysis of the network results showed that the AM activity of component quercetin, formononetin, calycosin, 7-O-methylisomucronulatol, and quercetin have a good binding activity with top ten screened targets, such as VEGFA, TNF, IL-6, MAPK, CCL3, NOS3, PTGS2, IL-1β, JUN, and EGFR. GO and KEGG analyses revealed that these targets were associated with inflammatory response, angiogenesis, oxidative stress reaction, rheumatoid arthritis, and other biological process.

CONCLUSIONS

This study demonstrated the multicomponent, multitarget, and multichannel characteristics of AM, which provided a novel approach for further research of the mechanism of AM in the treatment of DN.

Effects of Citrullus colocynthis L. in a rat model of diabetic neuropathy

OBJECTIVE

This study investigated the biochemical, histopathological and physiological effects of Citrullus colocynthis on peripheral neuropathy in rats with streptozotocin (STZ)-induced diabetes.

METHODS

Seventy adult male Sprague-Dawley rats were included in the present study. Diabetes was induced in 60 rats, with a single intraperitoneal injection of STZ (65 mg/kg). After 4 weeks, the diabetic rats were assessed for neuropathy. Then, the diabetic rats with neuropathy were randomly divided into 6 groups for a 4-week treatment with gabapentin, oral administration of C. colocynthis fruit pulp powder (100 and 300 mg/kg per day), topical preparations as oil-based solution and ointment, or placebo. Changes in metabolic, physiological, biochemical and histological parameters were considered as treatment outcomes.

RESULTS

Metabolic outcomes (body weight and blood glucose level) were improved in the C. colocynthis-treated groups as compared to placebo. Tail-flick and hot-plate tests also had lower latency in the C. colocynthis-treated groups. Measurement of oxidative stress markers (malondialdehyde, superoxide dismutase and catalase) showed the antioxidant effect of C. colocynthis. Histological evaluation of the sciatic nerve showed that C. colocynthis decreased the number of demyelinated and degenerated nerve fibers. Among the C. colocynthis-treated groups, the one receiving 100 mg/kg power per day orally had the best treatment outcomes.

CONCLUSION

The present study showed that C. colocynthis fruit, through its antioxidant and hypoglycemic activities, has a positive effect in the treatment of diabetic neuropathy.

VEGF-A and cardiac autonomic function in newly diagnosed type 2 diabetes mellitus: A cross-sectional study at a tertiary care center

Introduction:

Cardiac autonomic neuropathy (CAN) is a key complication of type 2 diabetes mellitus (Ty2DM). Vascular endothelial-derived growth factor (VEGF-A) plays a key role in diabetic macrovascular and microvascular complications. It is shown to be elevated in diabetic neuropathy and has the potential to serve as a biomarker in Ty2DM. We evaluated VEGF-A levels and cardiac autonomic function in newly diagnosed Ty2DM patients.

Materials and Methods:

Forty-four newly diagnosed patients (with symptoms within 1 year from the date of recruitment) were included in the study. Cardiac autonomic function was assessed using heart rate variability (HRV) and Ewing's battery tests. Ewing's scores were computed and tabulated. VEGF-A levels were estimated using enzyme-linked immunosorbent assay (ELISA).

Results:

The patients demonstrated normal responses to the reactivity tests. Ewing's scores were 0 (0-0) and 0 (0-0) for sympathetic and parasympathetic parameters, respectively. The autonomic tone was impaired as assessed by HRV parameters. VEGF-A levels were elevated (308.3 ± 167.2 pg/mL) when compared with the previous literature.

Discussion:

Impaired tone with normal reactivity was suggestive of early stage of autonomic neuropathy. Elevated VEGF-A levels may be attributed to a protective action of the factor seen in early stages of neuropathy in Ty2DM. Serial VEGF-A estimation in large cohorts of newly diagnosed diabetics may validate it as a biomarker in CAN seen in Ty2DM.