Avian riboflavin deficiency causes reliably reproducible peripheral nerve demyelination and, with vitamin supplementation, rapid remyelination.

Riboflavin deficiency produces severe peripheral neve demyelination in young, rapidly growing chickens. While this naturally-occurring vitamin B2 deficiency can cause a debilitating peripheral neuropathy, and mortality, in poultry flocks, it can also be a useful experimental animal model to study the pathogenesis of reliably reproducible peripheral nerve demyelination. Moreover, restitution of normal riboflavin levels in deficient birds results in brisk remyelination. It is the only acquired, primary, demyelinating tomaculous neuropathy described to date in animals. The only other substance that causes peripheral nerve demyelination similar to avian riboflavin deficiency is tellurium and the pathologic features of the peripheral neuropathy produced by this developmental neurotoxin in weanling rats are also described.

Revisiting the Role of Biologically Active Natural and Synthetic Compounds as an Intervention to Treat Injured Nerves.

Traumatic lesions in nerves present high incidence and may culminate in sensorimotor and/or autonomic dysfunctions or a total loss of function, affecting the patient's quality of life. Although the microenvironment favors peripheral nerve regeneration, the regenerative process is not always successful. Some herbs, natural products, and synthetic drugs have been studied as potential pro-regenerative interventions. We reviewed and discussed the most recent articles published over the last ten years in high impact factor journals. Even though most of the articles contemplated in this review were in vitro and animal model studies, those with herbs showed promising results. Most of them presented antioxidant and anti-inflammatory effects. Drugs of several pharmacological classes also showed optimistic outcomes in nerve functional recovery, including clinical trials. The results are hopeful; however, mechanisms of action need to be elucidated, and there is a need for more high-quality clinical studies. The study presents careful compilation of findings of dozens of compounds with consistent pro-regenerative evidence published in respected scientific journals. It may be valuable for health professionals and researchers in the field.

Chemotherapy-induced peripheral neuropathy (CIPN): current therapies and topical treatment option with high-concentration capsaicin.

Cancer diagnosis and treatment are drastic events for patients and their families. Besides psychological aspects of the disease, patients are often affected by severe side effects related to the cancer itself or as a result of therapeutic interventions. Particularly, chemotherapy-induced peripheral neuropathy (CIPN) is the most prevalent neurological complication of oral or intravenous chemotherapy. The disorder may require dose reduction of chemotherapy and is accompanied by multiple symptoms with long-term functional impairment affecting quality of life (QoL), e.g., sensory and functional deteriorations as well as severe pain. Although CIPN may reverse or improve after termination of the causative chemotherapy, approximately 30-40% of patients are faced with chronicity of the symptoms. Due to the advantages in cancer diagnosis and treatments, survival rates of cancer patients rise and CIPN may occur even more frequently in the future. In this review, we summarize current recommendations of leading national and international societies regarding prevention and treatment options in CIPN. A special focus will be placed on current evidence for topical treatment of CIPN with high-dose capsaicin. Finally, an algorithm for CIPN treatment in clinical practice is provided, including both pharmacologic and non-pharmacologic modalities based on the clinical presentation.

Clinical Characteristics of Peripheral Neuropathy in Eosinophilic Granulomatosis with Polyangiitis: A Retrospective Single-Center Study in China.

OBJECTIVE: To investigate clinical features, independent associated factors, treatment, and outcome of patients with peripheral neuropathy (PN) in eosinophilic granulomatosis with polyangiitis (EGPA). METHODS: We retrospectively analyzed clinical data of 110 EGPA patients from 2007 to 2019 in Peking Union Medical College Hospital. The independent factors associated with PN in EGPA were analyzed with univariate and multivariate logistic regressions. RESULTS: In EGPA with PN, paresthesia and muscle weakness were observed in 82% and 33% of patients, respectively. Both the upper and lower limbs were involved in 51% of patients. 30% of EGPA patients had symmetrical multiple peripheral neuropathy, whereas only 16.4% presented with mononeuritis multiplex. Compared to patients without PN, patients with PN had a higher erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor, Birmingham vasculitis activity score (BVAS), and positivity of myeloperoxidase-antineutrophil cytoplasmic antibodies (MPO-ANCA). Regarding manifestations, patients with PN tended to develop weight loss and arthritis or joint pain. Notably, ANCA positivity, arthritis or joint pain, and higher BVAS were found to be independent associated factors for PN in EGPA. Patients with PN more frequently need glucocorticoid pulses and intravenous infusion of cyclophosphamide. With the longest follow-up of 11.0 years, we found that age and cardiac involvement were risk factors for survival, and female was the protective factor. CONCLUSION: PN in EGPA frequently displays with symmetrical multiple peripheral neuropathy in China. Positive ANCA, arthritis or joint pain, and higher BVAS are the independent associated factors of PN in EGPA. Glucocorticoids with immunosuppressants are vital therapeutic strategy.

Evidence for a novel subcortical mechanism for posterior cingulate cortex atrophy in HIV peripheral neuropathy.

We previously reported that neuropathic pain was associated with smaller posterior cingulate cortical (PCC) volumes, suggesting that a smaller/dysfunctional PCC may contribute to development of pain via impaired mind wandering. A gap in our previous report was lack of evidence for a mechanism for the genesis of PCC atrophy in HIV peripheral neuropathy. Here we investigate if volumetric differences in the subcortex for those with neuropathic paresthesia may contribute to smaller PCC volumes, potentially through deafferentation of ascending white matter tracts resulting from peripheral nerve damage in HIV neuropathy. Since neuropathic pain and paresthesia are highly correlated, statistical decomposition was used to separate pain and paresthesia symptoms to determine which regions of brain atrophy are associated with both pain and paresthesia and which are associated separately with pain or paresthesia. HIV+ individuals (N = 233) with and without paresthesia in a multisite study underwent structural brain magnetic resonance imaging. Voxel-based morphometry and a segmentation/registration tool were used to investigate regional brain volume changes associated with paresthesia. Analysis of decomposed variables found that smaller midbrain and thalamus volumes were associated with paresthesia rather than pain. However, atrophy in the PCC was related to both pain and paresthesia. Peak thalamic atrophy (p = 0.004; MNI x = - 14, y = - 24, z = - 2) for more severe paresthesia was in a region with reciprocal connections with the PCC. This provides initial evidence that smaller PCC volumes in HIV peripheral neuropathy are related to ascending white matter deafferentation caused by small fiber damage observed in HIV peripheral neuropathy.

Understanding the multi-herbal composition of Buyang Huanwu Decoction: A review for better clinical use.

ETHNOPHARMACOLOGICAL RELEVANCE: Buyang Huanwu Decoction (BHD) is a multi-herbal composition commonly prescribed in the treatment of cerebrovascular diseases such as stroke. Although studies have been conducted at the cellular (in vitro), animal and human (in vivo) level, there was no detailed analysis on how the composition and proportion of BHD is modified according to target diseases. AIM OF STUDY: The purpose of this study is to investigate the composition and proportion of each herb in BHD to summarize how the original BHD was modified according to the target disease. MATERIALS AND METHODS: Electronic literature searches were performed in three databases, collecting sixty-eight studies for the final analysis. The studies were divided into three types: cell studies, animal experiments and clinical trial. In the analysis, the decoction formula including the composition and the weight proportion of the herbs in BHD used in the studies and the target diseases were examined. RESULTS: The result showed that in cell studies, the targets were mostly cell differentiation, cell injury and immune activation. In animal studies, cerebrovascular diseases such as cerebral ischemia were the most identified target diseases followed by nervous system and cardiovascular diseases. While the proportions of the herbs in BHD used in these studies were in general similar to the original formula, some studies reduced the amount of Astragali Radix to half of the original amount. Modified BHDs were used in four studies for cerebrovascular and peripheral nerve diseases. However, no significant correlation has been observed between the target diseases and the change of the proportion of the herbs in BHD. CONCLUSIONS: The most commonly used formula was the original composition of BHD, and modified BHDs were reported to be used to treat cerebrovascular and nervous diseases. Further studies about the effects of BHD by composition and proportion of herbs are needed in the future.

Scrambler therapy for chemotherapy neuropathy: a randomized phase II pilot trial.

INTRODUCTION: Chemotherapy-induced peripheral neuropathy (CIPN) is a prominent clinical problem, with limited effective therapies. Preliminary non-randomized clinical trial data support that Scrambler Therapy is helpful in this situation. METHODS: Patients were eligible if they had CIPN symptoms for at least 3 months and CIPN-related tingling or pain at least 4/10 in severity during the week prior to registration. They were randomized to receive Scrambler Therapy versus transcutaneous electrical nerve stimulation (TENS) for 2 weeks. Patient-reported outcomes (PROs) were utilized to measure efficacy and toxicity daily for 2 weeks during therapy and then weekly for 8 additional weeks. RESULTS: This study accrued 50 patients, 25 to each of the 2 study arms; 46 patients were evaluable. There were twice as many Scrambler-treated patients who had at least a 50% documented improvement during the 2 treatment weeks, from their baseline pain, tingling, and numbness scores, when compared with the TENS-treated patients (from 36 to 56% compared with 16-28% for each symptom). Global Impression of Change scores for "neuropathy symptoms," pain, and quality of life were similarly improved during the treatment weeks. Patients in the Scrambler group were more likely than those in the TENS group to recommend their treatment to other patients, during both the 2-week treatment period and the 8-week follow-up period (p < 0.0001). Minimal toxicity was observed. CONCLUSIONS: The results from this pilot trial were positive, supporting the conduct of further investigations regarding the use of Scrambler Therapy for treating CIPN.

Pathological Observation of Blood Stasis Syndrome in Non-diabetic Peripheral Neuropathies: A Retrospective Analysis Based on Nerve Biopsy.

OBJECTIVE: To investigate the pathological features of blood stasis syndrome (BSS) in non-diabetic peripheral neuropathy. METHODS: Clinical data of 31 patients with non-diabetic peripheral neuropathy who had undergone nerve biopsy during December 2004 and December 2010 in Xuanwu Hospital Capital Medical University were retrospectively analyzed. According to Chinese medicine (CM) syndrome differentiation and signs, 26 patients were blood stasis type and 5 patients were non-blood stasis type. Clinical and pathological data were compared in detail. RESULTS: Clinically, although both groups shared similar symptoms of limb numbness, weakness and sensory disturbances, the prevalence of neuralgia was much grievous in BSS group (73.1%, 26/31) compared with the non-BSS group (0%, 0/5). As for signs, dermal nutrients disturbance (84.6%, 22/26), dark or purple tongue (100.0%, 26/26), and sublingual varices (80.7%, 21/26) were more common in the BSS group than the non-BSS group (0%, 60%, 20%, respectively). The prevalence of qi deficiency cases (19/26) in the BSS group was significantly higher compared with the non-BSS group (1/5). The unique histological manifestations of BSS were axonal degeneration (16/26 vs 2/5 in non-BSS group), which was the hallmark of ischemia. Cases with BSS had prominent microangiopathy (61.5%, 16/26), manifested as epineurium vasculitis (inflammatory cell infiltrated to the vessel wall, obliteration and recanalization, vascular proliferation, extravascular hemosiderin deposition), angiotelectasis, proliferation and hyaline degeneration of endoneurium capillary. In the BSS group, impaired blood-nerve barrier was indicated by sub-perineurial edema (46.2%, 11/26) and endoneurial edema (15.4%, 4/26). The Renaut body (15.4%, 4/26) and amyloid deposition (3.8%, 1/26) found in the BSS group were absent in the non-BSS group. CONCLUSIONS: BBS was common in non-diabetic peripheral neuropathies. The nerves exhibited ischemic alteration of primary axon degeneration and secondary demyelination. The interstitial tissue revealed microcirculation impairment, blood-nerve barrier disturbance, amyloid deposition and proliferation changes. The high prevalence of qi deficiency also highlights the therapy of promotion of blood circulation and removal of blood stasis.

Electroacupuncture Alleviates Paclitaxel-Induced Peripheral Neuropathic Pain in Rats via Suppressing TLR4 Signaling and TRPV1 Upregulation in Sensory Neurons.

Paclitaxel-induced peripheral neuropathy is a common adverse effect during paclitaxel treatment resulting in sensory abnormalities and neuropathic pain during chemotherapy and in cancer survivors. Conventional therapies are usually ineffective and possess adverse effects. Here, we examined the effects of electroacupuncture (EA) on a rat model of paclitaxel-induced neuropathic pain and related mechanisms. EA robustly and persistently alleviated paclitaxel-induced pain hypersensitivities. Mechanistically, TLR4 (Toll-Like Receptor 4) and downstream signaling MyD88 (Myeloid Differentiation Primary Response 88) and TRPV1 (Transient Receptor Potential Vallinoid 1) were upregulated in dorsal root ganglion (DRGs) of paclitaxel-treated rats, whereas EA reduced their overexpression. Ca2+ imaging further indicated that TRPV1 channel activity was enhanced in DRG neurons of paclitaxel-treated rats whereas EA suppressed the enhanced TRPV1 channel activity. Pharmacological blocking of TRPV1 mimics the analgesic effects of EA on the pain hypersensitivities, whereas capsaicin reversed EA's effect. Spinal astrocytes and microglia were activated in paclitaxel-treated rats, whereas EA reduced the activation. These results demonstrated that EA alleviates paclitaxel-induced peripheral neuropathic pain via mechanisms possibly involving suppressing TLR4 signaling and TRPV1 upregulation in DRG neurons, which further result in reduced spinal glia activation. Our work supports EA as a potential alternative therapy for paclitaxel-induced neuropathic pain.

Safety and Effectiveness of Mist Antiaris, a Herbal Preparation for Treatment of Peripheral Neuropathy.

Mist Antiaris is a herbal decoction for treatment of nervous disorders. Safety and efficacy were evaluated in Sprague-Dawley rats and human patients, respectively. Acute toxicity was assessed by administration of a single 5000 mg/kg oral dose of decoction to a group of six rats. For subchronic toxicity, four groups of six rats each received water (control) or 10, 100, or 200 mg/kg oral doses of decoction daily for eight weeks. Body weight, serum, urine, and hematological profile of the animals in each group were monitored over the period. Effects of treatment on pentobarbital-induced sleeping time and histology of liver, lung, heart, and kidney tissue were assessed at the end of the study. There was no evidence of acute toxicity within 48 hours of the oral dose. Over the 8-week period, body weight increases in Mist Antiaris treatment groups were reduced relative to the control group. There were no significant differences in urine profile, serum biochemistry, hematological parameters, and pentobarbital-induced sleeping time. Tissue histology revealed no differences relative to controls. Assessment of efficacy was by retrospective review of data on patients who presented with peripheral neuropathy. Treatment resulted in 53.7 % of patients reporting complete resolution and 15.7 % showing reduction in neuropathic symptoms. The data demonstrate that there is no toxicity due to subchronic administration of Mist Antiaris in Sprague-Dawley rats. The reduction or resolution of neuropathic symptoms indicated by patents' file data provides evidence to suggest that Mist Antiaris has antineuropathic effects.

Chemotherapy-Induced Neuropathy and Drug Discovery Platform Using Human Sensory Neurons Converted Directly from Adult Peripheral Blood.

Chemotherapy-induced peripheral neuropathy (PN) is a disorder damaging the peripheral nervous system (PNS) and represents one of the most common side effects of chemotherapy, negatively impacting the quality of life of patients to the extent of withdrawing life-saving chemotherapy dose or duration. Unfortunately, the pathophysiological effects of PN are poorly understood, in part due to the lack of availability of large numbers of human sensory neurons (SNs) for study. Previous reports have demonstrated that human SNs can be directly converted from primitive CD34+ hematopoietic cells, but was limited to a small-scale product of SNs and derived exclusively from less abundant allogenic sources of cord or drug mobilized peripheral blood (PB). To address this shortcoming, we have developed and report detailed procedures toward the generation of human SN directly converted from conventionally drawn PB of adults that can be used in a high-content screening platform for discovery-based studies of chemotherapy agents on neuronal biology. In the absence of mobilization drugs, cryogenically preserved adult human PB could be induced to (i)SN via development through expandable neural precursor differentiation. iSNs could be transferable to high-throughput procedures suitable for high-content screening applicable to neuropathy for example, alterations in neurite morphology in response to chemotherapeutics. Our study provides the first reported platform using adult PB-derived iSNs to study peripheral nervous system-related neuropathies as well as target and drug screening potential for the ability to prevent, block, or repair chemotherapy-induced PN damage. Stem Cells Translational Medicine 2019;8:1180-1191.

Therapeutic effects of moxibustion simultaneously targeting Nrf2 and NF-κB in diabetic peripheral neuropathy.

Moxibustion is the main alternative medicine treatment that has been beneficial to diabetic peripheral neuropathy (DPN), a common complication secondary to diabetic microvascular injury. However, the underlying protective mechanism of moxibustion against neuroinflammation remains unclear. We hypothesized that moxibustion treats DPN by regulating the balance of nuclear factor-2 erythroid-related factor-2 (Nrf2)-nuclear factor-kappa light chain enhancer of B cells (NF-кB). In vivo, diabetes was induced in rats by injecting streptozotocin (STZ; 60 mg/kg; i.p.). Moxibustion was then applied to "Zusanli" (ST 36), "Guanyuan" (BL 26), and "Yishu" (EX-B 3) acupuncture points. Nerve conduction was detected. Serum interleukin (IL)-1ß, IL-6, and IL-8 levels were determined through enzyme-linked immunosorbent assay. NF-κB and Nrf2 proteins were examined through immunoblot analysis. The mRNA of NF-κB and Nrf2 was evaluated through RT-PCR. We found that the conduction velocity and amplitude of the action potentials of sciatic nerve conduction were reduced in the DPN model group but were rescued by moxibustion treatment. Moxibustion also improved the effect of DPN on other parameters, including ultrastructural changes, NF-κB and Nrf2 expression in the sciatic nerve, and serum IL-1ß, IL-6, and IL-8 levels. Our data suggested that moxibustion may alleviate neuroinflammation by inhibiting NF-κB and by activating Nrf2. Moxibustion may also provide therapeutic effects for patients with DPN by simultaneously targeting Nrf2 and NF-κB.

Neuroprotective Effects of an Aqueous Extract of Forsythia viridissima and Its Major Constituents on Oxaliplatin-Induced Peripheral Neuropathy.

The dried fruits of Forsythia viridissima have been prescribed to relive fever, pain, vomiting, and nausea in traditional medicine. Oxaliplatin (LOHP) is used to treat advanced colorectal cancer; however, it frequently induces peripheral neuropathies. This study was done to evaluate the neuroprotective effects of an aqueous extract of Forsythia viridissima fruits (EFVF) and its major constituents. Chemical constituents from EFVF were characterized and quantified with the UHPLC-diode array detector method, and three major constituents were identified as arctiin, matairesinol, and arctigenin. The in vitro cytotoxicity was measured by the Ez-cytox viability assay, and the in vivo neuroprotection activity was evaluated by a von Frey test in two rodent animal models that were administered LOHP. EFVF significantly alleviated the LOHP-induced mechanical hypersensitivity in the induction model. EFVF also prevented the induction of mechanical hyperalgesia by LOHP in the pre- and co-treatment of LOHP and EFVF. Consistently, EFVF exerted protective effects against LOHP-induced neurotoxicity as well as inhibited neurite outgrowths in PC12 and dorsal root ganglion cells. Among the major components of EFVF, arctigenin and matairesinol exerted protective effects against LOHP-induced neurotoxicity. Therefore, EFVF may be useful for relieving or preventing LOHP-induced peripheral neuropathy in cancer patients undergoing chemotherapy with LOHP.

Long-term neuropathy and quality of life in colorectal cancer patients treated with oxaliplatin containing adjuvant chemotherapy.

BACKGROUND: Oxaliplatin, combined with capecitabine (CAPOX) or infused 5-fluorouracil (FOLFOX), is standard of care in the adjuvant treatment of colorectal cancer (CRC). Prospective data on prevalence of oxaliplatin induced acute and long-term neuropathy in a real-life patient population and its effects on quality of life (QOL) and survival is limited, and scarce in CAPOX versus FOLFOX treated, especially in a subarctic climate. METHODS: One hundred forty-four adjuvant CRC patients (all 72 CAPOX cases and 72 matched FOLFOX controls) were analyzed regarding oxaliplatin induced sensory neuropathy, which was graded according to NCI-CTCAEv3.0. Ninety-two long-term survivors responded to the QOL (EORTC QLQ-C30) and Chemotherapy-Induced Peripheral Neuropathy (EORTC CIPN20) questionnaires and were interviewed regarding long-term neuropathy. RESULTS: Acute neurotoxicity was present in 94% (136/144) during adjuvant therapy and there was a significant association between acute neurotoxicity and long-term neuropathy (p < .001). Long-term neuropathy was present in 69% (grade 1/2/3/4 in 36/24/8/1%) at median 4.2 years. Neuropathy grades 2-4 did not influence global health status, but it was associated with decreased physical functioning (p = .031), decreased role functioning (p = .040), and more diarrhea (p = .021) in QLQ-C30 items. There were no differences in acute neurotoxicity, long-term neuropathy, or in QOL between CAPOX and FOLFOX treated. Neuropathy showed no pattern of variation according to starting and stopping month or treatment during winter. CONCLUSIONS: Neuropathy following oxaliplatin containing adjuvant chemotherapy is present in two-thirds, years after cessation, and impairs some QOL scales. There is no difference in severity of acute or long-term neuropathy between CAPOX and FOLFOX treated and QOL is similar. No seasonal variation in neuropathy was noted.

Alcohol-related peripheral neuropathy: a systematic review and meta-analysis.

The primary aim of this systematic review was to establish the prevalence, character, and risk factors of peripheral neuropathy amongst chronic alcohol abusers and to identify the most appropriate management strategies. In this review, possible pathogenetic mechanisms are also discussed. A systematic, computer-based search was conducted using the PubMed database. Data regarding the above parameters were extracted. 87 articles were included in this review, 29 case-control studies, 52 prospective/retrospective cohort studies and 2 randomised control trials, 1 cross sectional study, and 3 population-based studies. The prevalence of peripheral neuropathy amongst chronic alcohol abusers is 46.3% (CI 35.7- 57.3%) when confirmed via nerve conduction studies. Alcohol-related peripheral neuropathy generally presents as a progressive, predominantly sensory axonal length-dependent neuropathy. The most important risk factor for alcohol-related peripheral neuropathy is the total lifetime dose of ethanol, although other risk factors have been identified including genetic, male gender, and type of alcohol consumed. At present, it is unclear what the pathogenetic mechanisms for the development of neuropathy amongst those who chronically abuse alcohol are, and therefore, it is unknown whether it is attributed to the direct toxic effects of ethanol or another currently unidentified factor. There is presently sparse data to support a particular management strategy in alcohol-related peripheral neuropathy, but the limited data available appears to support the use of vitamin supplementation, particularly of B-vitamin regimens inclusive of thiamine.

A phase IIA trial of acupuncture to reduce chemotherapy-induced peripheral neuropathy severity during neoadjuvant or adjuvant weekly paclitaxel chemotherapy in breast cancer patients.

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is a common and potentially dose-limiting side-effect of neurotoxic chemotherapy for cancer patients. We evaluated the preliminary efficacy of acupuncture in preventing worsening CIPN in patients receiving paclitaxel. METHODS: In this phase IIA single-arm clinical trial, we screened stage I-III breast cancer patients receiving neoadjuvant/adjuvant weekly paclitaxel for development of CIPN. The primary objective was to assess acupuncture's efficacy in preventing the escalation of National Cancer Institute-Common Toxicity Criteria for Adverse Events (NCI-CTCAE), version 4.0, grade II CIPN to higher grades. Acupuncture was deemed worthy of further study if 23 or more of the 27 enrolled patients did not develop grade III CIPN. Outcome measures (NCI-CTCAE CIPN grade, Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity [FACT/GOG-Ntx], Neuropathic Pain Scale [NPS]) were obtained weekly during the intervention. RESULTS: Of 104 patients screened, 37 developed grade II CIPN (36%), and 28 (27%) enrolled into the intervention phase; one was removed due to protocol violation. Of the 27 patients receiving acupuncture, 26 completed paclitaxel treatment without developing grade III CIPN, meeting our prespecified success criteria for declaring acupuncture worthy of further study. FACT/GOG-Ntx and NPS scores remained stable during the intervention while continuing weekly paclitaxel. Acupuncture treatment was well tolerated; 4 of 27 (15%) patients reported grade I bruising. CONCLUSIONS: Acupuncture was safe and showed preliminary evidence of effectiveness in reducing the incidence of high grade CIPN during chemotherapy. A follow-up randomised controlled trial is needed to establish definitive efficacy in CIPN prevention for patients at risk.

Transcriptomic RNAseq drug screen in cerebrocortical cultures: toward novel neurogenetic disease therapies.

Rare monogenic diseases affect millions worldwide; although over 4500 rare disease genotypes are known, disease-modifying drugs are available for only 5% of them. The sheer number of these conditions combined with their rarity precludes traditional costly drug discovery programs. An economically viable alternative is to repurpose established drugs for rare diseases. Many genetic diseases result from increased or decreased protein activity and identification of clinically approved drugs which moderate this pathogenic dosage holds therapeutic potential. To identify such agents for neurogenetic diseases, we have generated genome-wide transcriptome profiles of mouse primary cerebrocortical cultures grown in the presence of 218 blood-brain barrier (BBB) penetrant clinic-tested drugs. RNAseq and differential expression analyses were used to generate transcriptomic profiles; therapeutically relevant drug-gene interactions related to rare neurogenetic diseases identified in this fashion were further analyzed by quantitative reverse transcriptase-polymerase chain reaction, western blot and immunofluorescence. We have created a transcriptome-wide searchable database for easy access to the gene expression data resulting from the cerebrocortical drug screen (Neuron Screen) and have mined this data to identify a novel link between thyroid hormone and expression of the peripheral neuropathy associated gene Pmp22. Our results demonstrate the utility of cerebrocortical cultures for transcriptomic drug screening, and the database we have created will foster further discovery of novel links between over 200 clinic-tested BBB penetrant drugs and genes related to diverse neurologic conditions.

Neuroprotective effects and UPLC-Q-TOF/MS-based active components identification of external applied a novel Wen-Luo-Tong microemulsion.

Chemotherapy induced neuropathy causes excruciating pain to cancer patients. Wen-Luo-Tong (WLT), a traditional Chinese medicinal compound, has been used to alleviate anti-cancer drug such as oxaliplatin-induced neuropathic pain for many years. However, the current route of administration of WLT is inconvenient and the active ingredients and mechanism of action of WLT are still unclear. To address these issues, we developed a novel formulation of WLT (W/O microemulsion) for the ease of application. New ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) methods were employed for analysis of the ingredients. We identified seven ingredients that penetrated through the skin into the Franz cell receptor solution and four of those ingredients were retained in skin tissue when WLT microemulsion was applied. We tested the microemulsion formulation on an oxaliplatin-induced neuropathy rat model and showed that this formulation significantly decreased oxaliplatin-induced mechanical hyperalgesia responses. Schwann cells (SCs) viability experiment in vitro was studied to test the protective effect of the identified seven ingredients. The result showed that Hydroxysafflor Yellow A, icariin, epimedin B and 4-dihydroxybenzoic acid significantly increased the viability of SCs after injured by Oxaliplatin. Our report presents the first novel formulation of WLT with neuroprotective effect and ease of use, which has potential for clinical applications.

Editor's Highlight: Multiparametric Image Analysis of Rat Dorsal Root Ganglion Cultures to Evaluate Peripheral Neuropathy-Inducing Chemotherapeutics.

Chemotherapy-induced peripheral neuropathy (CIPN) is a major, dose-limiting adverse effect experienced by cancer patients. Advancements in mechanism-based risk mitigation and effective treatments for CIPN can be aided by suitable in vitro assays. To this end, we developed a multiparametric morphology-centered rat dorsal root ganglion (DRG) assay. Morphologic alterations in subcellular structures of neurons and non-neurons were analyzed with an automated microscopy system. Stains for NeuN (a neuron-specific nuclear protein) and Tuj-1 (ß-III tubulin) were used to identify neuronal cell nuclei and neuronal cell bodies/neurites, respectively. Vimentin staining (a component of Schwann cell intermediate filaments) was used to label non-neuronal supporting cells. Nuclei that stained with DAPI, but lacked NeuN represented non-neuronal cells. Images were analyzed following 24 h of continuous exposure to CIPN-inducing agents and 72 h after drug removal to provide a dynamic measure of recovery from initial drug effects. Treatment with bortezomib, cisplatin, eribulin, paclitaxel or vincristine induced a dose-dependent loss of neurite/process areas, mimicking the 'dying back' degeneration of axons, a histopathological hallmark of clinical CIPN in vivo. The IC50 for neurite loss was within 3-fold of the maximal clinical exposure (Cmax) for all five CIPN-inducing drugs, but was >4- or ≥ 28-fold of the Cmax for 2 non-CIPN-inducing agents. Compound-specific effects, eg, neurite fragmentation by cisplatin or bortezomib and enlarged neuronal cell bodies by paclitaxel, were also observed. Collectively, these results support the use of a quantitative, morphologic evaluation and a DRG cell culture model to inform risk and examine mechanisms of CIPN.

Comparison of sensory tests and neuronal quantity of peripheral nerves between streptozotocin (STZ)-induced diabetic rats and paclitaxel (PAC)-treated rats.

Although diabetic peripheral neuropathy (DPN) and chemotherapy-induced peripheral neuropathy (CIPN) are different disease entities, they share similar neuropathic symptoms that impede quality of life for these patients. Despite having very similar downstream effects, there have been no direct comparisons between DPN and CIPN with respect to symptom severity and therapeutic responses. We compared peripheral nerve damage due to hyperglycemia with that caused by paclitaxel (PAC) treatment as represented by biochemical parameters, diverse sensory tests, and immunohistochemistry of cutaneous and sciatic nerves. The therapeutic effects of alpha-lipoic acid and DA-9801 were also compared in the two models. Animals were divided into seven groups (n = 7-10) as follows: normal, diabetes (DM), DM + alpha-lipoic acid 100 mg/kg (ALA), DM + DA-9801 (100 mg/kg), paclitaxel-treated rat (PAC), PAC + ALA (100 mg/kg), and PAC + DA-9801 (100 mg/kg). The sensory thresholds of animals to mechanical, heat, and pressure stimuli were altered by both hyperglycemia and PAC when compared with controls, and the responses to sensory tests were different between both groups. There were no significant differences in the biochemical markers of blood glutathione between DM and PAC groups (p > .05). Quantitative comparisons of peripheral nerves by intraepidermal nerve fiber density (IENFD) analysis indicated that the DM and PAC groups were similar (6.18 ± 1.03 vs. 5.01 ± 2.57). IENFD was significantly improved after ALA and DA-9801 treatment in diabetic animals (7.6 ± 1.28, 7.7 ± 1.28, respectively, p < .05) but did not reach significance in the PAC-treated groups (6.05 ± 1.76, 5.66 ± 1.26, respectively, p > .05). Sciatic nerves were less damaged in the PAC-treated groups compared with the DM groups with respect to axonal diameter and area (8.60 ± 1.14 µm vs. 6.66 ± 1.07 µm, and 59.04 ± 15.16 µm2 vs. 35.71 ± 11.2 µm2, respectively, p < .05). Based on these results, the neuropathic manifestation and therapeutic responses of DPN may be different from other peripheral neuropathies. Therefore, specific pathogenic consideration according to peripheral neuropathy classification in addition to common treatments needs to be developed for management strategies of peripheral neuropathies.