10 kHz spinal cord stimulation improves metrics of spinal sensory processing in a male STZ rat model of diabetes.

To explore why clinical 10 kHz spinal cord stimulation (10 kHz SCS) might improve neurological function in a model of painful diabetic neuropathy (PDN), the short-term behavioral, electrophysiological, and histological effects of 10 kHz SCS were studied using adult male streptozotocin (STZ)-induced diabetic Sprague-Dawley rats. Four testing groups were established: Naïve controls (N = 8), STZ controls (N = 7), STZ+Sham SCS (N = 9), and STZ+10 kHz SCS (N = 11). After intraperitoneal injection (60 mg/kg) of STZ caused the rats to become hyperglycemic, SCS electrodes were implanted in the dorsal epidural space over the L5-L6 spinal segments in the STZ+Sham SCS and STZ+10 kHz SCS groups and were stimulated for 14 days. The von Frey filament paw withdrawal threshold was measured weekly. At termination, animals were anesthetized and the electrophysiologic response of dorsal horn neurons (receptive field size, vibration, radiant warmth) of the ipsilateral foot was measured. Tissue from the plantar paw surface was obtained post-euthanization for intraepidermal nerve fiber density measurements. In comparison to other control groups, while no significant effect of 10 kHz SCS on peripheral intraepidermal nerve fiber density was observed, 10 kHz SCS 'normalized' the central neural response to vibration, receptive field, and paw withdrawal threshold, and elevated the neural response to tissue recovery from warm stimuli. These results suggest that short-term, low intensity 10 kHz SCS operates in the spinal cord to ameliorate compromised sensory processing, and may compensate for reduced peripheral sensory functionality from chronic hyperglycemia, thereby treating a broader spectrum of the sensory symptoms in diabetic neuropathy.

Effect of Graded Motor Imagery on Quality of Life, Pain, Kinesiophobia and Pain Catastrophization in Painful Diabetic Neuropathy: Study Protocol for 3-Arm Randomized Controlled Trial.

Background: Painful Diabetic Neuropathy (PDN) occurs as a complication in 88% of all patients with diabetic peripheral neuropathy. The intensity of pain has a direct impact on the function, levels of anxiety, kinesiophobia, fear of pain and fear of hypoglycemia, leading to reduction in the levels of physical activity. Objective: The objective of this study will be to study the effects of Graded Motor Imagery (GMI), Graded exposure and Conventional Therapy on Quality of Life (QoL), pain, kinesiophobia, pain catastrophization and anxiety in participants with PDN. Methods: This RCT will have three parallel groups with 30 participants in each group, calculated assuming partial eta squared value of 0.14, effect size of 0.403 at 85% power of the study and α error of 0.05 using G-power software. Setting: The study will be conducted at OPD & IPD of a Tertiary Care Hospital in Goa-India. Participants: Participants with Type 1 or Type II diabetes in the age group of 18-75 years having a score of 3 or more on DN-4 will be included in the study. Intervention: Group A will receive GMI, Group B will be given graded exposure & group C will be undergoing conventional physical therapy treatment. The intervention will last for 8 weeks and follow-up will be done after one month. Primary Outcome Measure: assessment using RAND SF-36, Visual Analogue Scale, Tampa Scale for Kinesiophobia and Pain catastrophization will be done at 3 time points. Conclusion: This high quality RCT will provide important information about the efficacy of GMI on QoL, pain levels, pain catastrophization, kinesiophobia and anxiety. It will provide evidence for the use of cognitive intervention for pain and its associated factors, consistent with the biopsychosocial model of pain.

Efficacy and safety of hyperbaric oxygen therapy for diabetes peripheral neuropathy: A systematic review and meta-analysis.

BACKGROUND: Diabetes peripheral neuropathy (DPN) is mainly treated with diabetes as a whole, and there is no targeted treatment. Some studies have reported that adjuvant hyperbaric oxygen therapy (HBOT) for DPN has achieved a good effect, our study aimed to evaluate the clinical efficacy and safety of HBOT for DPN and provide reference for the clinic by using a systematic review and meta-analysis. METHODS: A comprehensive search was conducted across several databases, including PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Internet Database, Chinese BioMedical Database, China Scientific Journal Database, and Wanfang Database, for relevant randomized controlled trials published before July 2022. The population, intervention, comparison, outcomes, study design criteria were used to guide the selection of studies. Meta-analysis was performed using RevMan 5.4 and STATA 14.0, with odds ratios and mean differences along with 95% confidence intervals serving as measures of effect size. RESULTS: Fourteen randomized controlled trials were included in the final analysis, comprising 675 patients in the HBOT group and 648 in the standard therapy (ST) group. The HBOT group demonstrated a significantly higher effective treatment rate compared to the ST group (P < .001). Additionally, the HBOT group showed significant improvements in motor nerve conduction velocity (MNCV) and sensory nerve conduction velocity (SNVC) across multiple nerves: median nerve (PMNCV < 0.001, PSNCV = 0.001), ulnar nerve (PMNCV = 0.02, PSNCV < 0.001), peroneal nerve (PMNCV < 0.001, PSNCV < 0.001), and tibial nerve (PMNCV = 0.001, PSNCV = 0.008). Six adverse events were reported in the HBOT group, while no adverse events occurred in the ST group, with no significant difference between the 2 groups. Publication bias was identified in some outcome variables through funnel plots, Begger test, and Egger test. CONCLUSIONS: HBOT significantly enhances treatment efficacy and nerve conduction velocity in patients with DPN, with few adverse events, making it a safe and effective adjunctive therapy for DPN.

Transcutaneous vagus nerve stimulation has no anti-inflammatory effect in diabetes.

Chronic inflammation is associated with diabetes and contributes to the development and progression of micro- and macrovascular complications. Transcutaneous vagus nerve stimulation (tVNS) has been proposed to reduce levels of circulating inflammatory cytokines in non-diabetics by activating the cholinergic anti-inflammatory pathway. We investigated the anti-inflammatory potential of tVNS as a secondary endpoint of a randomized controlled trial in people with diabetes (NCT04143269). 131 people with diabetes (type 1: n = 63; type 2: n = 68), gastrointestinal symptoms and various degrees of autonomic neuropathy were included and randomly assigned to self-administer active (n = 63) or sham (n = 68) tVNS over two successive study periods: (1) Seven days with four daily administrations and, (2) 56 days with two daily administrations. Levels of systemic inflammatory cytokines (IL-6, IL-8, IL-10, TNF-α, IFN-γ) were quantified from blood samples by multiplex technology. Information regarding age, sex, diabetes type, and the presence of cardiac autonomic neuropathy (CAN) was included in the analysis as possible confounders. No differences in either cytokine were seen after study period 1 and 2 between active and sham tVNS (all p-values > 0.08). Age, sex, diabetes type, presence of CAN, and baseline levels of inflammatory cytokines were not associated with changes after treatment (all p-values > 0.07). A tendency towards slight reductions in TNF-α levels after active treatment was observed in those with no CAN compared to those with early or manifest CAN (p = 0.052). In conclusion, tVNS did not influence the level of systemic inflammation in people with diabetes.

Case report: Comprehensive management of painful diabetic neuropathy-Addressing opioid-induced hyperalgesia through multimodal approaches.

RATIONALE: Diabetic neuropathy is a prevalent and debilitating complication of diabetes, necessitating effective pain management strategies. While pharmacological treatments, including opioids, are commonly employed, they pose significant challenges due to the risk of developing opioid-induced hyperalgesia (OIH). This case report aims to illustrate the efficacy of a comprehensive, multidisciplinary approach in managing painful diabetic neuropathy complicated by OIH. PATIENT CONCERNS: A 64-year-old male patient presented to the Pain Treatment Clinic with severe lower limb pain due to diabetic polyneuropathy. He had a history of multiple comorbidities. DIAGNOSES: The patient's condition and physical examination suggested the presence of opioid-induced hyperalgesia (OIH). Despite the increased dose of opioids, the patient did not report significant constipation or breathing difficulties but experienced drowsiness and dry mouth. A diagnosis of opioid and benzodiazepine dependence was made. INTERVENTIONS: The treatment plan involved the initiation of pregabalin and duloxetine, gradual reduction of opioid use, and psychiatric support for addiction management. OUTCOMES: Over 12 months, the patient experienced significant pain reduction and minimal adverse effects. LESSONS: Effective management of OIH involves gradual opioid tapering and a multimodal therapeutic approach. However, the optimal treatment strategies and the frequency of OIH occurrence remain areas of uncertainty, relying heavily on clinical expertise and individualized patient care. Further research is needed to refine these treatment strategies and improve patient outcomes.

Diabetic peripheral neuropathy based on Schwann cell injury: mechanisms of cell death regulation and therapeutic perspectives.

Diabetic peripheral neuropathy (DPN) is a complication of diabetes mellitus that lacks specific treatment, its high prevalence and disabling neuropathic pain greatly affects patients' physical and mental health. Schwann cells (SCs) are the major glial cells of the peripheral nervous system, which play an important role in various inflammatory and metabolic neuropathies by providing nutritional support, wrapping axons and promoting repair and regeneration. Increasingly, high glucose (HG) has been found to promote the progression of DPN pathogenesis by targeting SCs death regulation, thus revealing the specific molecular process of programmed cell death (PCD) in which SCs are disrupted is an important link to gain insight into the pathogenesis of DPN. This paper is the first to review the recent progress of HG studies on apoptosis, autophagy, pyroptosis, ferroptosis and necroptosis pathways in SCs, and points out the crosstalk between various PCDs and the related therapeutic perspectives, with the aim of providing new perspectives for a deeper understanding of the mechanisms of DPN and the exploration of effective therapeutic targets.

Unraveling the RAGE-NF-κB pathway: implications for modulating inflammation in diabetic neuropathy through photobiomodulation therapy.

Diabetic peripheral neuropathy (DPN) is a primary complication observed in diabetes that severely affects quality of life. Recent evidence suggests that photobiomodulation (PBM) is a promising therapy against painful conditions and nerve damage. However, the effects of PBM on DPN remains mostly unknown. In the present study, we investigated the efficacy of PBM therapy in modulating proinflammatory cytokine expression in both central and peripheral nervous systems of rats with Streptozotocin (STZ)-induced type 1 diabetes. Male Wistar rats were allocated into control (naïve), diabetic (STZ), and treatment (STZ + PBM) groups. A single intraperitoneal (i.p.) injection of STZ (85 mg/kg) was administered for the induction of diabetes. Animals were subjected to 10 treatment sessions, every other day. The results herein presented indicate that PBM treatment diminishes Receptor for Advanced Glycation End-products (RAGE) and Nuclear Factor Kappa B (NF-Ï°B) expression in peripheral nervous system and suppresses TNF-α expression in central nervous system tissues. Furthermore, PBM-therapy in diabetic rats also induces increased levels of the anti-inflammatory protein IL-10 in both peripheral and central nervous system. Collectively, our findings demonstrate compelling evidence that PBM-therapy modulates cytokine dynamics and influences RAGE/NF-Ï°B axis in a STZ-induced model of type 1 diabetes.

Electroacupuncture Alleviates Streptozotocin-Induced Diabetic Neuropathic Pain via the TRPV1-Mediated CaMKII/CREB Pathway in Rats.

Diabetic neuropathic pain (DNP) is a diabetic complication that causes severe pain and deeply impacts the quality of the sufferer's daily life. Currently, contemporary clinical treatments for DNP generally exhibit a deficiency in effectiveness. Electroacupuncture (EA) is recognized as a highly effective and safe treatment for DNP with few side effects. Regrettably, the processes via which EA alleviates DNP are still poorly characterized. Transient receptor potential vanilloid 1 (TRPV1) and phosphorylated calcium/calmodulin-dependent protein kinase II (p-CaMKII) are overexpressed on spinal cord dorsal horn (SCDH) in DNP rats, and co-localization is observed between them. Capsazepine, a TRPV1 antagonist, effectively reduced nociceptive hypersensitivity and downregulated the overexpression of phosphorylated CaMKIIα in rats with DNP. Conversely, the CaMKII inhibitor KN-93 did not have any impact on TRPV1. EA alleviated heightened sensitivity to pain caused by nociceptive stimuli and downregulated the level of TRPV1, p-CaMKIIα, and phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB) in DNP rats. Intrathecal injection of capsaicin, on the other hand, reversed the above effects of EA. These findings indicated that the CaMKII/CREB pathway on SCDH is located downstream of TRPV1 and is affected by TRPV1. EA alleviates DNP through the TRPV1-mediated CaMKII/CREB pathway.

Systematic review of translational insights: Neuromodulation in animal models for Diabetic Peripheral Neuropathy.

Diabetic Peripheral Neuropathy (DPN) is a prevalent and debilitating complication of diabetes, affecting a significant proportion of the diabetic population. Neuromodulation, an emerging therapeutic approach, has shown promise in the management of DPN symptoms. This systematic review aims to synthesize and analyze the current advancements in neuromodulation techniques for the treatment of DPN utilizing studies with preclinical animal models. A comprehensive search was conducted across multiple databases, including PubMed, Scopus, and Web of Science. Inclusion criteria were focused on studies utilizing preclinical animal models for DPN that investigated the efficacy of various neuromodulation techniques, such as spinal cord stimulation, transcranial magnetic stimulation, and peripheral nerve stimulation. The findings suggest that neuromodulation significantly alleviated pain symptoms associated with DPN. Moreover, some studies reported improvements in nerve conduction velocity and reduction in nerve damage. The mechanisms underlying these effects appeared to involve modulation of pain pathways and enhancement of neurotrophic factors. However, the review also highlights the variability in methodology and stimulation parameters across studies, highlighting the need for standardization in future research. Additionally, while the results are promising, the translation of these findings from animal models to human clinical practice requires careful consideration. This review concludes that neuromodulation presents a potentially effective therapeutic strategy for DPN, but further research is necessary to optimize protocols and understand the underlying molecular mechanisms. It also emphasizes the importance of bridging the gap between preclinical findings and clinical applications to improve the management of DPN in diabetic patients.

Different Types of Cell Death in Diabetic Neuropathy: A Focus on Mechanisms and Therapeutic Strategies.

Diabetic neuropathy (DN) is a common complication of diabetes, affecting over 50% of patients, leading to significant pain and a burden. Currently, there are no effective treatments available. Cell death is considered a key factor in promoting the progression of DN. This article reviews how cell death is initiated in DN, emphasizing the critical roles of oxidative stress, mitochondrial dysfunction, inflammation, endoplasmic reticulum stress, and autophagy. Additionally, we thoroughly summarize the mechanisms of cell death that may be involved in the pathogenesis of DN, including apoptosis, autophagy, pyroptosis, and ferroptosis, among others, as well as potential therapeutic targets offered by these death mechanisms. This provides potential pathways for the prevention and treatment of diabetic neuropathy in the future.

Peroneal Nerve Entrapment in Diabetes Mellitus.

This narrative mini-review discusses the association between peroneal nerve entrapment (PEN) and diabetes mellitus (DM). Generally, PEN is not a common cause of peripheral neuropathy in DM. Poor glycaemic control and DM duration are powerful risk factors for PEN. Underlying mechanisms involve neurodegeneration and entrapment of the peroneal nerve. Patients tend to present with chronic leg pain, gradual foot drop, steppage gait, or weakness of ankle dorsiflexion. Electrodiagnostic and imaging studies are very useful in diagnosis to determine the level at which entrapment occurs. Treatment varies based on the aetiology and severity of symptoms. It is initially conservative. Surgical nerve decompression management is required when entrapment is refractory to non-operative options.

Enteric neuropathy in diabetes: Implications for gastrointestinal function.

Diabetes, commonly known for its metabolic effects, also critically affects the enteric nervous system (ENS), which is essential in regulating gastrointestinal (GI) motility, secretion, and absorption. The development of diabetes-induced enteric neuropathy can lead to various GI dysfunctions, such as gastroparesis and irregular bowel habits, primarily due to disruptions in the function of neuronal and glial cells within the ENS, as well as oxidative stress and inflammation. This editorial explores the pathophysiological mechanisms underlying the development of enteric neuropathy in diabetic patients. Additionally, it discusses the latest advances in diagnostic approaches, emphasizing the need for early detection and intervention to mitigate GI complications in diabetic individuals. The editorial also reviews current and emerging therapeutic strategies, focusing on pharmacological treatments, dietary management, and potential neuromodulatory interventions. Ultimately, this editorial highlights the necessity of a multidisciplinary approach in managing enteric neuropathy in diabetes, aiming to enhance patient quality of life and address a frequently overlooked complication of this widespread disease.

Expert opinion on screening, diagnosis and management of diabetic peripheral neuropathy: a multidisciplinary approach.

The proposed expert opinion aimed to address the current knowledge on conceptual, clinical, and therapeutic aspects of diabetic peripheral neuropathy (DPN) and to provide a guidance document to assist clinicians for the best practice in DPN care. The participating experts consider the suspicion of the disease by clinicians as a key factor in early recognition and diagnosis, emphasizing an improved awareness of the disease by the first-admission or referring physicians. The proposed "screening and diagnostic" algorithm involves the consideration of DPN in a patient with prediabetes or diabetes who presents with neuropathic symptoms and/or signs of neuropathy in the presence of DPN risk factors, with careful consideration of laboratory testing to rule out other causes of distal symmetric peripheral neuropathy and referral for a detailed neurological work-up for a confirmative test of either small or large nerve fiber dysfunction in atypical cases. Although, the first-line interventions for DPN are currently represented by optimized glycemic control (mainly for type 1 diabetes) and multifactorial intervention (mainly for type 2 diabetes), there is a need for individualized pathogenesis-directed treatment approaches for DPN. Alpha-lipoic acid (ALA) seems to be an important first-line pathogenesis-directed agent, given that it is a direct and indirect antioxidant that works with a strategy targeted directly against reactive oxygen species and indirectly in favor of endogenous antioxidant capacity for improving DPN conditions. There is still a gap in existing research in the field, necessitating well-designed, robust, multicenter clinical trials with sensitive endpoints and standardized protocols to facilitate the diagnosis of DPN via a simple and effective algorithm and to track progression of disease and treatment response. Identification of biomarkers/predictors that would allow an individualized approach from a potentially disease-modifying perspective may provide opportunities for novel treatments that would be efficacious in early stages of DPN, and may modify the natural course of the disease. This expert opinion document is expected to increase awareness among physicians about conceptual, clinical, and therapeutic aspects of DPN and to assist them in timely recognition of DPN and translating this information into their clinical practice for best practice in the management of patients with DPN.

Exploring Mitochondrial Interactions with Pulsed Electromagnetic Fields: An Insightful Inquiry into Strategies for Addressing Neuroinflammation and Oxidative Stress in Diabetic Neuropathy.

Pulsed electromagnetic fields (PEMFs) are recognized for their potential in regenerative medicine, offering a non-invasive avenue for tissue rejuvenation. While prior research has mainly focused on their effects on bone and dermo-epidermal tissues, the impact of PEMFs on nervous tissue, particularly in the context of neuropathy associated with the diabetic foot, remains relatively unexplored. Addressing this gap, our preliminary in vitro study investigates the effects of complex magnetic fields (CMFs) on glial-like cells derived from mesenchymal cell differentiation, serving as a model for neuropathy of the diabetic foot. Through assessments of cellular proliferation, hemocompatibility, mutagenicity, and mitochondrial membrane potential, we have established the safety profile of the system. Furthermore, the analysis of microRNAs (miRNAs) suggests that CMFs may exert beneficial effects on cell cycle regulation, as evidenced by the upregulation of the miRNAs within the 121, 127, and 142 families, which are known to be associated with mitochondrial function and cell cycle control. This exploration holds promise for potential applications in mitigating neuropathic complications in diabetic foot conditions.

Diabetic Neuropathy: A Guide to Pain Management.

PURPOSE OF REVIEW: Diabetic neuropathy is a common complication of diabetes mellitus (DM) and can affect up to 50% of DM patients during their lifetime. Patients typically present with numbness, tingling, pain, and loss of sensation in the extremities. Since there is no treatment targeting the underlying mechanism of neuropathy, strategies focus on preventative care and pain management. RECENT FINDINGS: Up to 69% of patients with diabetic neuropathy receive pharmacological treatment for neuropathic pain. The United States Food and Drug Administration (FDA) confirmed four drugs for painful diabetic neuropathy (PDN): pregabalin, duloxetine, tapentadol, and the 8% capsaicin patch. Nonpharmacological treatments such as spinal cord stimulation (SCS) and transcutaneous electrical nerve stimulation (TENS) both show promise in reducing pain in DM patients. Despite the high burden associated with PDN, effective management remains challenging. This update covers the background and management of diabetic neuropathy, including its epidemiology, pathogenesis, preventative care, and current therapeutic strategies.

Review and Evaluation of European National Clinical Practice Guidelines for the Treatment and Management of Active Charcot Neuro-Osteoarthropathy in Diabetes Using the AGREE-II Tool Identifies an Absence of Evidence-Based Recommendations.

Background: Charcot neuro-osteoarthropathy (CNO) is a rare but devastating complication of diabetes associated with high rates of morbidity; yet, many nonfoot specialists are unaware of it, resulting in missed and delayed diagnosis. Clinical practice guidelines (CPGs) have proven useful in improving quality of care and standardizing practice in diabetes and diabetic foot care. However, little is known about the consistency in recommendations for identification and management of active CNO. Aim: The aim of this study is to review European national diabetes CPGs for the diagnosis and management of active CNO and to assess their methodological rigor and transparency. Methods: A systematic search was performed to identify diabetes national CPGs across Europe. Guidelines in any language were reviewed to explore whether they provided a definition for active CNO and recommendations for diagnosis, monitoring, and management. Methodological rigor and transparency were assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE-II) tool, which comprises 23 key items organized within six domains with an overall guideline assessment score of ≥ 60% considered to be of adequate quality to recommend use. Each guideline was assessed by two reviewers, and inter-rater agreement (Kendall's W) was calculated for AGREE-II scores. Results: Seventeen CPGs met the inclusion criteria. Breadth of CNO content varied across guidelines (median (IQR) word count: 327; Q1 = 151; Q3 = 790), and 53% provided a definition for active CNO. Recommendations for diagnosis and monitoring were provided by 82% and 53%, respectively, with offloading being the most common management recommendation (88%). Four guidelines (24%) reached threshold for recommendation for use in clinical practice (≥ 60%) with the scope and purpose domain scoring highest (mean (SD): 67%, ± 23%). The remaining domains had average scores ranging between 19% and 53%. Inter-rater agreement was strong (W = 0.882; p < 0.001). Conclusions: European national CPGs for diabetes provide limited recommendations on active CNO. All guidelines showcased deficits in their methodology, suggesting that more rigorous methods should be employed for diabetes CPG development across Europe.

Effects of Computer-based Balance Exercises on Balance, Pain, Clinical Presentation and Nerve Function in Patients With Diabetic Peripheral Neuropathy: A Randomized Controlled Study.

OBJECTIVE: To evaluate the use of a computer-based biodex balance exercise system (BBS) on balance, neuropathic pain, clinical presentation and nerve function in patients with diabetic peripheral neuropathy (DPN). METHODS: A total of 32 participants with DPN were randomly assigned in a 1:1 ratio to an intervention group (IG) or control group (CG). The IG performed exercises using the BBS twice weekly for 8 weeks, while CG were informed regarding diabetes self-management. At baseline and after study completion, participants underwent balance (postural stability and fall risk) and neuropathic pain assessment (DN4 questionnaire) and were screened using the Michigan Neuropathy Screening Instrument and nerve conduction test. RESULTS: Among the baseline participants, 14 in the IG and 13 in the CG completed the study. Balance training improved postural stability (overall, p<0.001), fall risk (p<0.001), neuropathic pain (p=0.01) and symptoms (p<0.001), and clinical presentation (p=0.02), but not nerve function, within the IG. At follow-up, IG displayed significantly improved stability (p<0.001) and fall risk (p=0.02) and decreased neuropathic symptoms (p=0.01) compared to the CG. CONCLUSION: Computer-based balance exercises improve balance, pain, and clinical presentation of DPN, but not nerve function, in patients with DPN. CLINICALTRIALS: gov ID: NCT05255497.