Characterization of the Metabolic Proteome of Serum From Patients With Diabetic Distal Symmetric Polyneuropathy.

AIMS: The pathophysiological of diabetic distal symmetric polyneuropathy (DSPN) remains to be elucidated and there are no diagnostic or prognostic biomarkers for the condition. In this explorative proteomic study, metabolic proteome profiling of serum in patients with/without DSPN was analyzed. We aimed to discover proteins with different abundance ranges through proximity extension assay (PEA) technology. METHODS: Temperature quantitative sensory testing (QST) and electromyography (EMG) were used to access the small- and large-fiber function of all participants, respectively. The metabolic proteome profile of serum was analyzed using PEA technology (Olink Target 96 METABOLISM panel). RESULTS: We evaluated serum from patients without DSPN (n = 27), with small-fiber neuropathy (SFN, n = 25) and with mixed small- and large-fiber neuropathy (MSLFN, n = 24). Fifteen proteins, which were especially related to immune response, insulin resistance, and lipid metabolism, were significantly different between patients without DSPN and with MSLFN. Besides, seven proteins, especially related to extracellular structure organization, were significantly different between serum from patients with SFN and with MSLFN. What's more, serum from patients without DSPN showed that three proteins, related to immune response, altered significantly compared to serum from patients with SFN. CONCLUSIONS: This was the first study that characterized the metabolic proteomic profile of serum in DSPN patients by analyzing a panel of 92 metabolic proteins using PEA technology.

Serum Spexin Level Is Negatively Associated With Peripheral Neuropathy and Sensory Pain in Type 2 Diabetes.

Background: Spexin is a novel peptide hormone and has shown antinociceptive effects in experimental mice. This study is aimed at evaluating the association of serum spexin level with diabetic peripheral neuropathy (DPN) and related pain in a Chinese population. Methods: We enrolled 167 type 2 diabetes mellitus (T2DM) including 56 patients without DPN (non-DPN), 67 painless DPN, and 44 painful DPN. Serum spexin was measured using ELISA. Logistic regression models were performed to analyze the independent effects of spexin on prevalence of DPN and painful DPN. In streptozotocin (STZ)-induced diabetic mice, mechanical pain threshold was measured using electronic von Frey aesthesiometer. Human peripheral blood mononuclear cells (PBMCs) were isolated and further stimulated with lipopolysaccharide without or with spexin. The gene expression was assayed by qPCR. Results: Compared with non-DPN, serum spexin level decreased in painless DPN and further decreased in painful DPN. The odds of DPN was associated with low spexin level in T2DM, which was similar by age, sex, BMI, and diabetes duration, but attenuated in smokers. The odds of having pain was associated with decreased spexin level in DPN, which was similar by age, sex, smoking status, and diabetes duration, but attenuated in normal weight. Furthermore, we observed that mechanical pain threshold increased in spexin-treated diabetic mice. We also found that lipopolysaccharide treatment increased the mRNA level of TNF-α, IL-6, and MCP-1 in human PBMCs, while spexin treatment prevented this increase. Conclusions: These results suggested that spexin might serve as a protective factor for diabetes against neuropathology and pain-related pathogenesis.

Estimated glucose disposal rate predicts the risk of diabetic peripheral neuropathy in type 2 diabetes: A 5-year follow-up study.

BACKGROUND: Insulin resistance is associated with chronic complications of diabetes, including diabetic peripheral neuropathy (DPN). Estimated glucose disposal rate (eGDR), calculated by the common available clinical factors, was proved to be an excellent tool to measure insulin resistance in large patient population. Few studies have explored the association between eGDR and DPN longitudinally. Therefore, we performed the current study to analyze whether eGDR could predict the risk of DPN. METHODS: In this prospective study, 366 type 2 diabetes (T2DM) subjects without DPN were enrolled from six communities in Shanghai in 2011-2014 and followed up until 2019-2020. Neuropathy was assessed by Michigan Neuropathy Screening Instrument (MSNI) at baseline and at the end of follow-up. FINDINGS: After 5.91 years, 198 of 366 participants progressed to DPN according to MNSI examination scores. The incidence of DPN in the low baseline eGDR (eGDR < 9.15) group was significantly higher than in the high baseline eGDR (eGDR ≥ 9.15) group (62.37% vs. 45.56%, p = .0013). The incidence of DPN was significantly higher in patients with sustained lower eGDR level (63.69%) compared with those with sustained higher eGDR level (35.80%). Subjects with low baseline eGDR (eGDR < 9.15) had significantly higher risk of DPN at the end of follow-up (odds ratio = 1.75), even after adjusting for other known DPN risk factors. CONCLUSIONS: The 5-year follow-up study highlights the importance of insulin resistance represented by eGDR in the development of DPN in T2DM. Diabetic patients with low eGDR are more prone to DPN and, therefore, require more intensive screening and more attention.

The recovery time of hypothalamic-pituitary-adrenal axis after curative surgery in Cushing's disease and its related factor.

PURPOSE: Patients with Cushing's disease (CD) experienced transient central adrenal insufficiency (CAI) after successful surgery. However, the reported recovery time of hypothalamic-pituitary-adrenal (HPA) axis varied and the related factors which could affect recovery time of HPA axis had not been extensively studied. This study aimed to analyze the duration of CAI and explore the factors affecting HPA axis recovery in post-operative CD patients with biochemical remission. METHODS: Medical records of diagnosis with CD in Huashan Hospital were reviewed between 2014 and 2020. 140 patients with biochemical remission and regular follow-up after surgery were enrolled in this retrospective cohort study according to the criteria. Demographic details, clinical and biochemical information at baseline and each follow-up (within 2 years) were collected and analyzed. RESULTS: Overall, 103 patients (73.6%) recovered from transient CAI within 2 years follow-up and the median recovery time was 12 months [95% confidence intervals (CI): 10-14]. The age was younger and midnight ACTH at baseline was significantly lower, while the TT3 and FT3 levels were significantly higher in patients with recovered HPA compared to patients with persistent CAI at 2-year follow-up (p < 0.05). In persistent CAI group, more patients underwent partial hypophysectomy. TT3 at diagnosis was an independent related factor of the recovery of HPA axis, even after adjusting for gender, age, duration, surgical history, maximum tumor diameter, surgical strategy, and postoperative nadir serum cortisol level (p = 0.04, OR: 6.03, 95% CI: 1.085, 22.508). Among patients with unrecovered HPA axis at 2-year follow-up, 23 CAI patients (62%) were accompanied by multiple pituitary axis dysfunction besides HPA axis, including hypothyroidism, hypogonadism, or central diabetes insipidus. CONCLUSION: HPA axis recovered in 73.6% of CD patients within 2 years after successful surgery, and the median recovery time was 12 months. TT3 level at diagnosis was an independent related factor of postoperative recovery of HPA axis in CD patients. Moreover, patients coexisted with other hypopituitarism at 2-year follow-up had a high probability of unrecovered HPA axis.

Glycogen synthesis kinase-3ß involves in the analgesic effect of liraglutide on diabetic neuropathic pain.

AIMS: Explore whether Glycogen synthesis kinase-3ß (GSK3ß) involved in the analgesic effect of liraglutide on diabetic neuropathic pain (DNP). METHODS: DNP was induced by streptozocin (STZ) in WT and GSK3ß(S9A) mice, which carried a constitutively active form of GSK3ß. DNP mice were intracerebroventricularly injected with liraglutide 5 weeks after STZ injection. The behavior of neuropathic pain was evaluated 2 h after drugs administration. The microglial activation and the expression of NOD-like receptor protein 3 (NLRP3) in microglia in cortex were evaluated. The role of GSK3ß in the inhibitory effect of liraglutide on the NLRP3 inflammasome was explored in BV2 microglia. RESULTS: Intracerebroventricular administration of liraglutide significantly relieved neuropathic pain and inhibited the activation of cortical microglia in WT mice with DNP. But the effect of liraglutide disappeared in GSK3ß(S9A) mice. In BV2 microglia, GSK3ß inhibitor significantly suppressed NLRP3 inflammasome activation. And activating GSK3ß through GSK3ß(S9A) lentivirus significantly blocked the inhibitory effect of liraglutide on NLRP3 inflammasome in BV2 microglia. Intracerebroventricular administration of liraglutide significantly inhibited the expression of NLRP3 in cortex microglia of DNP group in WT mice but failed in GSK3ß(S9A) mice. CONCLUSION: GSK3ß involves in the analgesic effect of liraglutide on DNP through NLRP3 inflammasome in microglia.

The hypothalamic-pituitary-gonad axis in male Cushing's disease before and after curative surgery.

OBJECTIVE: Gonadal and sexual disturbances are commonly encountered in patients with Cushing's disease. Nevertheless, the prevalence of hypogonadism in male Cushing's disease, the risk factors as well as the recovery time have been scarcely reported. Therefore, we aimed to explore the prevalence of hypogonadism at baseline and its determinants. In addition, the recovery time of hypogonadism and risk factors for unrecovered gonadal axis in male Cushing's disease with biochemical remission were investigated. METHODS: We reviewed medical records of males with Cushing's disease managed between 2010 and 2020. Fifty-two male patients were enrolled according to the criteria. Each case attained biochemical remission after transsphenoidal surgery. Demographic details, clinical features, 24-hour UFC, hormonal profile [serum PRL, FSH, LH, TT, ACTH, cortisol, TT4/FT4, TT3/ FT3, TSH and IGF-1] were measured at baseline and during follow-up. The maximal tumor diameter on MRI was recorded at diagnosis. RESULTS: Hypogonadotropic hypogonadism was observed in thirty-nine patients (75%) at diagnosis. Total testosterone was negatively correlated with ACTH and 24-hour UFC. Midnight serum ACTH level at diagnosis was significantly associated with hypogonadism after adjusting for confounding factors. Thirty-two (80%) patients achieved eugonadism within 12 months after the surgery, of which twenty-eight (87.5%) achieved eugonadism within 3 months. Seven patients were persistently hypogonadal during the follow-up (≥1 year), mainly due to the hypopituitarism as a complication of the therapies such as surgery. CONCLUSION: Hypogonadotropic hypogonadism is frequent in male Cushing's disease, but it is reversible in most cases within one-year follow-up after remission.

Glucagon-like peptide-1 receptor agonist attenuates diabetic neuropathic pain via inhibition of NOD-like receptor protein 3 inflammasome in brain microglia.

AIMS: We aimed to explore the evidence of brain microglia activation in diabetic neuropathic pain (DNP) and the effect and mechanism of glucagon-like peptide-1 receptor agonist (GLP-RA) on DNP via brain microglia. METHODS: Brain microglia activation was observed in DNP rats by positron emission tomography/computed tomography. The behavior of neuropathic pain was assessed in DNP rats after intracerebroventricular administration of GLP-1RA or microglial inhibitor minocycline. RNA sequencing was performed to explore the target of GLP-1RA on brain microglia. NOD-like receptor protein 3 (NLRP3) expression in brain microglia was evaluated in mentioned-above DNP rats, and the activation of NLRP3 inflammasome was analyzed in microglia treated with GLP-1RA. RESULTS: Microglia were activated in the cortex and thalamus of DNP rats. The thermal and mechanical allodynia were alleviated in DNP rats via intracerebroventricular administration of GLP-1RA or minocycline. And the activation of brain microglia was attenuated in DNP rats by intracerebroventricular administration of GLP-1RA. The expression of NLRP3 in brain microglia, which was found by RNA sequencing, was reduced in DNP rats by administration of GLP-1RA. Furthermore, GLP-1RA attenuated NLRP3 inflammasome activation in microglia triggered by LPS. CONCLUSION: GLP-1RA could alleviate DNP, possibly mediated by the suppression of brain microglia NLRP3 inflammasome activation.

Liver fibrosis is independently associated with diabetic peripheral neuropathy in type 2 diabetes mellitus.

AIMS/INTRODUCTION: Non-alcoholic fatty liver disease and type 2 diabetes mellitus are closely related, and often occur simultaneously in patients. Type 2 diabetes increases the risk of diabetic peripheral neuropathy, resulting in intolerable pain and extremity amputation that reduces the quality of life. However, the role of non-alcoholic fatty liver disease in the pathogenesis of diabetic peripheral neuropathy remains unclear. Thus, we evaluated the correlation of liver fibrosis and steatosis, which are representative histological morphologies of non-alcoholic fatty liver disease, with diabetic peripheral neuropathy in type 2 diabetes patients. MATERIALS AND METHODS: Five hundred twenty individuals with type 2 diabetes were recruited. All the patients were detected nerve conduction study for diabetic peripheral neuropathy and fibro touch for liver steatosis and fibrosis. Correlation of DPN with liver steatosis and fibrosis were analysed with binary logistic analysis. RESULTS: Among the 520 patients, the prevalence of liver steatosis, fibrosis and diabetic peripheral neuropathy was 63.0% (n = 328), 18.1% (n = 94) and 52.1% (n = 271), respectively. The prevalence of diabetic peripheral neuropathy was significantly elevated in patients with liver steatosis (55.7 vs 44.9%, P = 0.03) and fibrosis (61.5 vs 50%, P = 0.04), and it increased as liver stiffness measurement increased. Additionally, both hepatic steatosis (odds ratio 1.48, 95% confidence interval 1.04-2.11, P = 0.03) and fibrosis (odds ratio 1.60, 95% confidence interval 1.02-2.51, P = 0.04) were correlated with diabetic peripheral neuropathy. After adjusting for age, sex, weight, height, body mass index, waist hip ratio, duration of type 2 diabetes, blood glucose, homeostatic model assessment of insulin resistance, blood pressure, serum lipid, liver enzyme, urea, uric acid, creatinine and inflammatory factors, liver fibrosis remained associated with diabetic peripheral neuropathy (odds ratio 2.24, 95% confidence interval 1.11-4.53, P = 0.02). CONCLUSIONS: The prevalence of diabetic peripheral neuropathy was elevated in patients with liver steatosis and fibrosis. Liver fibrosis was also independently associated with an increased risk of diabetic peripheral neuropathy.

Decreased amino acids in the brain might contribute to the progression of diabetic neuropathic pain.

AIMS: The pathophysiological alteration of diabetic neuropathic pain (DNP) in brain is unclear. Here we aimed to explore the metabolomic characteristics of brain in rats over the progression of DNP through metabolomic analysis. METHODS: Adult rats were randomly divided into control group and DNP group. Body weight, blood glucose and behavioral assessment of neuropathic pain were measured every week after streptozotocin (STZ) injection. Finally, the brains of 2 rats from control group and 6 rats from DNP group were removed every 4 weeks after STZ injection for metabolomics analysis. RESULTS: After 4 weeks of STZ-injection, the rats with diabetes developed DNP, which was characterized as mechanical allodynia and thermal nociception. As for metabolomic analysis, differentially expressed metabolites (DE metabolites) showed a dynamic alteration over the development of DNP and affected several KEGG pathways associated with amino acid metabolism. Furthermore, the expression of l-Threonine, l-Methionine, d-Proline, l-Lysine and N-Acetyl-l-alanine were significantly decreased at all time points of DNP group. The amino acids which were precursor of analgesic neurotransmitters were downregulated over the progression of DNP, including l-tryptophan, l-histidine and l-tyrosine. CONCLUSIONS: The impairment of amino acid metabolism in brain might contribute to the progression of DNP through decreasing analgesic neurotransmitters.

Proinflammatory cytokines predict the incidence of diabetic peripheral neuropathy over 5 years in Chinese type 2 diabetes patients: A prospective cohort study.

BACKGROUND: Inflammation has been implicated in the pathogenesis of diabetic peripheral neuropathy (DPN) as suggested in various cross-sectional studies. However, more convincing prospective studies in diabetes patients are scarce. Therefore, we aimed to evaluate whether proinflammatory cytokines could predict the incidence of DPN through a prospective study with a five-year follow-up. METHODS: We followed up 315 patients with diabetes who did not have DPN, recruited from five community health centers in Shanghai in 2014, for an average of 5.06 years. Based on the integrity of blood samples, 106 patients were selected to obtain the proinflammatory cytokines. Plasma markers of proinflammatory cytokines at baseline included interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), vascular endothelial growth factor (VEGF), and intercellular adhesion molecule 1 (ICAM-1). Neuropathy was assessed by MSNI at baseline and during follow-up. FINDINGS: Among the 106 chosen patients, 63 developed DPN after 5.06±1.14 years of follow-up. The baseline plasma levels of TNF-α, IL-6, and ICAM-1 were higher in the neuropathic group (p<0.05). In multivariate models, increased plasma levels of TNF-α (hazard ratio, HR: 8.74 [95% confidence interval, CI: 1.05-72.68]; p <0.05) and ICAM-1 (HR 23.74 [95% CI:1.47-383.81]; p<0.05) were both associated with incident DPN, after adjusting for known DPN risk factors. INTERPRETATION: Increased plasma levels of proinflammatory factors, especially TNF-α and ICAM-1, predicted the incidence of DPN over 5 years in Chinese diabetes patients, but larger longitudinal studies are required for confirmation. FUNDING: National Natural Science Foundation of China, Shanghai Talent Development Fund Program, Shanghai Shenkang Hospital Developing Center Clinical Scientific and Technological Innovation Program, Shanghai Science and Technology Committee Program, Shanghai General Hospital Program of Chinese traditional and Western medicine combination and Shanghai Municipal Commission of Health and Family Planning Clinical Research Project.

Self-Reported Depressive Symptoms Might be Associated with Sudomotor Dysfunction in Chinese T2DM Patients.

AIMS: To determine the relationships of sudomotor functions, nerve conductions and self-reported depressive symptoms in Chinese type 2 diabetes (T2DM) patients. METHODS: T2DM patients in a single community health center were included in this study. Demographic, medical and laboratory data were collected. Michigan Neuropathy Screening Instrument (MNSI) examination was conducted in all patients. SUDOSCAN test and Point-of-care Nerve Conduction Device (DPN-check) were conducted and all the patients finished the Patient Health Questionnaire-9 (PHQ-9). RESULTS: A total of 162 T2DM patients (74 males and 88 females) were included. The mean age was 69.0±7.2 years and the mean course of diabetes was 10.5±8.0 years with a mean HbA1c level of 7.3±1.4%. Thirty of them (18.5%) had self-reported depressive symptoms (PHQ-9 scores≥5). Diabetic peripheral neuropathy (DPN) was diagnosed according to the MSNI examination in 74 patients. Electrochemical skin conductance (ESC) values of both hands and feet were significantly lower in patients with depressive symptoms (Hands ESC: 60.63±18.92 vs. 67.64±16.02 µS, p<0.05; Feet ESC: 59.60 ± 15.19 vs. 66.19±14.99 µS, p<0.05). The proportion of patients with moderate to severe depressive symptoms were significantly higher in those with ESC values<60 µS (13.33% vs. 3.846%, p<0.05). Hands ESC values were negatively related to PHQ-9 scores (r =- 0.168, p<0.05). After adjusting for variables, hands and feet ESC values remained negatively related with depressive symptoms (ß =- 0.036 and-0.038, p<0.05). Female were positively related to depressive symptoms with odds ratio 3.4 (95%CI 1.1-10.5, p<0.05). CONCLUSION: Self-reported depressive symptoms might be associated with sudomotor dysfunction in Chinese T2DM patients.

Age as an Independent Risk Factor for Diabetic Peripheral Neuropathy in Chinese Patients with Type 2 Diabetes.

Type 2 diabetes mellitus (T2DM) is more prevalent in aging populations. Older adults with diabetes have higher rates of macro and micro vascular complications. Our study assessed whether age is an independent factor for both large and small nerve dysfunctions in Chinese patients with T2DM. This cross-sectional study involved a total of 950 patients with type 2 diabetes (mean age: 60.01±12.30 years). Diabetic peripheral neuropathy (DPN) was assessed according to clinical symptoms and physical examinations by using neuropathy symptom score (NSS), the neuropathy disability score (NDS), Michigan Neuropathy Screening Instrument (MNSI score), vibration perception threshold (VPT) and SUDOSCAN test. By using independent logistic regression model, we showed that age was an independent risk factor of DPN (odds ratio [OR] = 1.036, 95% confidence interval [CI] 1.018-1.054, P< 0.01). T2DM patients over 71 years had a higher risk of DPN determined by using NSS/NDS (OR= 2.087; 95% CI 1.112-3.918; P <0.05), MNSI (OR=1.922; 95% CI 1.136-3.252; P<0.05), VPT (OR=3.452; 95%CI 1.052-11.332; P<0.05) and SUDOSCAN (OR=1.922; 95%CI 1.136-3.252; P<0.05) as diagnostic criteria respectively. The results of spline analysis showed a non-linearly positive association between age and OR of DPN. Individuals with 40, 50, 60, and 70 years old had LnOR of 1.22 (95%CI: 0.44- 2.00), 1.79(95%CI: 0.67- 2.91), 2.29 (95% CI: 0.98- 3.59), and 2.67(95% CI: 1.38-3.96) in DPN risk compared to T2DM patients with 19 years old, respectively. All of the above results in our study suggested age as an independent risk factor for the development of diabetic neuropathy in T2DM patients is significantly associated with the occurrence of both small and large nerve dysfunction, independent of other risk factors.

Quantitative analysis of corneal nerve fibers in type 2 diabetics with and without diabetic peripheral neuropathy: Comparison of manual and automated assessments.

AIMS: To examine and compare fully-automated and manually measured corneal nerve fiber parameters in type 2 diabetes mellitus (T2DM) patients with and without diabetic peripheral neuropathy (DPN). METHODS: A total of 128 T2DM subjects and 24 healthy controls underwent neuropathy assessment and bilateral corneal confocal microscopy (CCM). Five representative nerve fiber images were selected for each participant and analyzed manually and with fully-automated software. Corneal nerve fiber length (CNFL), branch density (CNBD), and fiber density (CNFD) were examined. RESULTS: Manual and full-automated methods for the whole cohort were significantly positive correlated for CNFL, CNBD and CNFD (r = 0.818, 0.845, 0.457, all P < 0.001). Analysis of agreement between the two measurements using Bland-Altman method showed a bias of 2.05 mm/mm2 (95% limits of agreement: -2.03 mm/mm2, 6.13 mm/mm2), 1.62 no./mm2 (95% limits of agreement: -17.92 no./mm2, 21.17 no./mm2), and 16.0 no./mm2 (95% limits of agreement: -0.14 no./mm2, 32.14 no./mm2) for CNFL, CNBD and CNFD respectively. A progressive decrease in manual and full-automated CNFL, CNBD and CNFD accompanied with the occurrence of DPN, The fully-automated method slightly underestimated corneal nerve fiber parameters. CONCLUSIONS: This study demonstrated strong correlations between manual and fully-automated CNFL and CNBD, but not CNFD. Fully-automated corneal nerve fiber parameter quantification may be a fast, objective way to detect DPN.

Low serum phosphate and magnesium levels are associated with peripheral neuropathy in patients with type 2 diabetes mellitus.

AIMS: To determine the relationship of serum phosphate, serum magnesium and peripheral nerve function in patients with type 2 diabetes mellitus (T2DM). METHODS: A total of 254 patients diagnosed with T2DM were included. Peripheral nerve function was evaluated by nerve conduction study with the use of electromyography. Composite z scores of conduction velocity, latency, and amplitude were constructed, respectively. Demographic, medical and laboratory data including serum phosphate and magnesium were collected. RESULTS: Serum phosphate and serum magnesium levels were significantly lower in patients with diabetic peripheral neuropathy (DPN) (P < 0.01). And the percentages of DPN patients were lower in high tertile of serum phosphate and serum magnesium (P < 0.05). Furthermore, composite z score of conduction velocity (CV) (P = 0.012) were positively associated with serum phosphate levels and the composite z score of amplitude (P < 0.001) and CV (P = 0.041) were positively associated with serum magnesium levels. After adjusting potential related factors (age, gender, smoking, diabetes duration, body mass index, systolic blood pressure, glycated hemoglobin, total cholesterol, estimated glomerular filtration rate), serum levels of phosphate and magnesium were still related to status of DPN in logistic regression (P < 0.05). CONCLUSION: Lower serum phosphate and magnesium significantly correlated with parameters of nerve conduction in T2DM patients. Serum phosphate and magnesium might underlie the pathophysiologic features of DPN.

Easier operation and similar power of 10 g monofilament test for screening diabetic peripheral neuropathy.

Objective The 10 g Semmes-Weinstein monofilament evaluation (SWME) of 4 sites on each foot is recommended for distal symmetric polyneuropathy screening and diagnosis. A similar method has been proposed to diagnose 'high-risk' (for ulceration) feet, using 3 sites per foot. This study compared the effectiveness of SWME for testing 3, 4 and 10 sites per foot to identify patients with diabetic neuropathy. Methods We included 3497 subjects in a SWME of 10 sites; records from the 10-site SWME were used for a SWME of 3 and 4 sites. Neuropathy symptom scores and neuropathy deficit scores were evaluated to identify patients with diabetic peripheral neuropathy. Results The sensitivities of the 10 g SWME for 3, 4 and 10 sites were 17.8%, 19.0% and 22.4%, respectively. The Kappa coefficients for the SWME tests of 3, 4 and 10 sites were high (range: 0.78-0.93). Conclusions There were no significant differences in the effectiveness of 3-, 4- and 10-site SWME testing for diabetic peripheral neuropathy screening. SWME testing of 3 sites on each foot may be sufficient to screen for diabetic neuropathy.

Corneal confocal microscopy as a non-invasive test to assess diabetic peripheral neuropathy.

OBJECTIVE: To evaluate the efficacy of corneal confocal microscopy (CCM) as a non-invasive test to assess diabetic peripheral neuropathy in Chinese patients diagnosed with type 2 diabetes. RESEARCH DESIGN AND METHODS: Diabetic distal symmetric polyneuropathy (DSPN) and its severity degrees were assessed based on the modified Toronto diagnostic criteria in 128 patients with type 2 diabetes (No DSPN [n = 49], mild DSPN [n = 43], moderate-to-severe DSPN [n = 36]) and 24 age-matched controls. CCM was also examined in all enrolled subjects. Corneal nerve fiber length (CNFL), corneal nerve branch density (CNBD) and corneal nerve fiber density (CNFD) were analyzed by Fiji imaging analysis software. The efficacy of CCM as a non-invasive test to assess diabetic peripheral neuropathy was determined. RESULTS: CNFL was 17.99 ±â€¯0.66, 15.82 ±â€¯0.64, 14.98 ±â€¯0.63, and 12.49 ±â€¯0.93 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNFL in type 2 diabetes patients with no, mild, and moderate-to-severe DSPN demonstrated a significant reduction than in healthy controls (P = .012, .003 and <.001, respectively). CNFL in patients with moderate-to-severe DSPN was significantly shorter than in patients with no or mild DSPN (P < .001 and .004, respectively). CNBD was 41.48 ±â€¯3.35, 33.02 ±â€¯2.50, 30.91 ±â€¯2.33, and 18.00 ±â€¯2.33 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNBD in healthy control was significantly higher than in type 2 diabetes patients with no, mild, and moderate-to-severe DSPN (P = .036, 0.016 and < .001, respectively). CNBD in patients with moderate-to-severe DSPN was significantly lower than in patients with no or mild DSPN (P < .001 for both). CNFD was 35.32 ±â€¯1.18, 35.68 ±â€¯1.10, 34.54 ±â€¯1.12, and 32.28 ±â€¯1.76 in healthy controls, T2DM patients with no, mild, and moderate-to-severe DPN, respectively. CNFD did not differ among the four groups. In an analysis that divided CNFL, CNFD and CNBD into quartiles, there were no significant differences in electromyography findings and vibration perception threshold among the 4 groups; however, significant differences were seen in the positive distribution of temperature perception measurements following CNFL and CNBD stratification (P = .001 and < .001, respectively). CONCLUSION: CCM might be a non-invasive method for detecting DSPN and its severity degree in Chinese patients diagnosed with type 2 diabetes.

Association of SUDOSCAN Values with Vibration Perception Threshold in Chinese Patients with Type 2 Diabetes Mellitus.

AIMS/INTRODUCTION: SUDOSCAN has been proved to be an efficient method in detecting diabetic microvascular complications. In this study, we determine to detect the possible relationship between vibration perception threshold (VPT) and cardiac autonomic neuropathy (CAN) values produced by SUDOSCAN. MATERIALS AND METHODS: A total of 920 Chinese patients with T2DM were enrolled in the study. Spearman correlation analysis and multivariate regression analysis were performed to determine the relation between CAN and VPT values. Mean VPT values across the CAN value tertiles were analyzed stratified by HbA1c status. RESULTS: In the study, we discovered a relatively high correlation between CAN value and both VPT values from dorsal feet and toes. Multivariate regression analyses also showed a significant relation between VPT and CAN values after adjusting all covariates. The mean value of VPT decreased across the SUDOSCAN-CAN value quartiles in both groups, and it was higher in patients with HbA1C > 9% than in patients with HbA1C < 9% across all quartiles of the SUDOSCAN-CAN except for the VPT mean in the low quartile of the SUDOSCAN-CAN value. CONCLUSIONS: All these results suggested that SUDOSCAN-CAN result was associated with VPT value which indicated a probable link between VPT value and cardiovascular autonomic dysfunction.

SUDOSCAN, an effective tool for screening chronic kidney disease in patients with type 2 diabetes.

SUDOSCAN is a non-invasive method of measuring peripheral small fiber and autonomic nerve activity by detection of abnormal sweat gland function through electrochemical skin conductance. It has been reported to be an effective screening tool in early detection of microvascular type 2 diabetes mellitus (T2DM) complications including diabetic neuropathy and nephropathy in recent studies. However, previous studies used estimated glomerular filtration rate (eGFR) as the golden standard, which has a 90% chance of being within 30% of the measured GFR at best. No relevant study has been performed in the Chinese population concerning SUDOSCAN in the screening of diabetic nephropathy (DN) in comparison with GFR. In this cross-sectional study, SUDOSCAN was performed in 176 Chinese patients with T2DM between September 2014 and September 2015. It was found that the SUDOSCAN test had a sensitivity of 57.8% and a specificity of 100% to detect chronic kidney disease at a cut-off SUDOSCAN-DN score of 59.5. The area under receiver operating characteristic curve for DN was 0.85 [95% confidence interval (CI), 0.76-0.93] compared with 0.84 for eGFRMDRD (MDRD, modification of diet in renal disease; 95% CI, 0.71-0.98) and 0.77 for eGFREPI (EPI, epidemiology collaboration; 95% CI, 0.68-0.87). Patients with DN score <59.5 had a significantly lower GFR level (P<0.001) and significantly older age (P<0.001), longer duration of T2DM (P<0.001) and higher risk of diabetic complications, including diabetic neuropathy (P<0.001) and peripheral vascular disease (P<0.05). These results suggested that SUDOSCAN may be useful for detecting patients at risk of impaired renal function as part of a screening program in the Chinese population with T2DM.

Neutrophil-to-lymphocyte ratio is associated with diabetic peripheral neuropathy in type 2 diabetes patients.

OBJECTIVE: Diabetic peripheral neuropathy (DPN) had been demonstrated as a chronic inflammation state and one of the most common complications of type 2 diabetes mellitus (T2DM). Neutrophil-to-lymphocyte ratio (NLR) is a novel marker to reflect many kinds of chronic inflammation disease including diabetes. We aim to evaluate the association between NLR and DPN and to determine whether NLR could be a new indicator of DPN in type 2 diabetes patients. METHODS: We retrospect the consecutive medical files of T2DM patients. Nerve conduction velocity (NCV), vibration perception threshold (VPT) and the data for complete blood count were recorded. Patients were divided into tertiles based on admission NLR values. Clinical parameters were firstly compared among groups. Then, logistic regression and ROC analysis were performed. RESULTS: Percentages of DPN were 42.60%, 54.97% and 65.50%, in the low, middle and high tertile, respectively (n=72, 94 and 112, p<0.05). VPT values were 13.75±7.97, 15.01±9.60 and 16.78±10.92, respectively, (p<0.05). NCV in different nerves decreased with the increase of NLR (p<0.05). After adjusting potential related factors, NLR was still related to status of DPN in the logistic regression (r=1.743, p=0.001). Area under ROC was 0.619 (p<0.001). CONCLUSION: The present study showed that T2DM patients with higher NLR levels might be more likely to develop peripheral neuropathy complication. NLR levels grow with the increase of NCV and VPT results. As a predictor of DPN, NLR could be used in clinical practice to help doctors understand the level of DPN progression.

Iron-Dependent Enzyme Catalyzes the Initial Step in Biodegradation of N-Nitroglycine by Variovorax sp. Strain JS1663.

Nitramines are key constituents of most of the explosives currently in use and consequently contaminate soil and groundwater at many military facilities around the world. Toxicity from nitramine contamination poses a health risk to plants and animals. Thus, understanding how nitramines are biodegraded is critical to environmental remediation. The biodegradation of synthetic nitramine compounds such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) has been studied for decades, but little is known about the catabolism of naturally produced nitramine compounds. In this study, we report the isolation of a soil bacterium, Variovorax sp. strain JS1663, that degrades N-nitroglycine (NNG), a naturally produced nitramine, and the key enzyme involved in its catabolism. Variovorax sp. JS1663 is a Gram-negative, non-spore-forming motile bacterium isolated from activated sludge based on its ability to use NNG as a sole growth substrate under aerobic conditions. A single gene (nnlA) encodes an iron-dependent enzyme that releases nitrite from NNG through a proposed ß-elimination reaction. Bioinformatics analysis of the amino acid sequence of NNG lyase identified a PAS (Per-Arnt-Sim) domain. PAS domains can be associated with heme cofactors and function as signal sensors in signaling proteins. This is the first instance of a PAS domain present in a denitration enzyme. The NNG biodegradation pathway should provide the basis for the identification of other enzymes that cleave the N-N bond and facilitate the development of enzymes to cleave similar bonds in RDX, nitroguanidine, and other nitramine explosives.IMPORTANCE The production of antibiotics and other allelopathic chemicals is a major aspect of chemical ecology. The biodegradation of such chemicals can play an important ecological role in mitigating or eliminating the effects of such compounds. N-Nitroglycine (NNG) is produced by the Gram-positive filamentous soil bacterium Streptomyces noursei This study reports the isolation of a Gram-negative soil bacterium, Variovorax sp. strain JS1663, that is able to use NNG as a sole growth substrate. The proposed degradation pathway occurs via a ß-elimination reaction that releases nitrite from NNG. The novel NNG lyase requires iron(II) for activity. The identification of a novel enzyme and catabolic pathway provides evidence of a substantial and underappreciated flux of the antibiotic in natural ecosystems. Understanding the NNG biodegradation pathway will help identify other enzymes that cleave the N-N bond and facilitate the development of enzymes to cleave similar bonds in synthetic nitramine explosives.