The general immunopharmacology of levamisole

Magnetic particles (Fe3O4) magnify ion transfer processes at the electrified liquid-liquid interface. Case study: Levamisole detection

This article describes the effect of non-stabilized magnetic particles Fe3O4 (nanoparticles aggregates) addition to the aqueous phase of the polarized liquid-liquid interface (LLI) on the interfacial ion transfer processes. LLI was formed between 1,2-dichloroethane and water solutions (1,2 DCE)|water. The synthesis of Fe3O4 magnetic particles (MPs) was achieved by the co-precipitation method, after which their appearance, size of aggregates, and zeta potential were assessed. All electrochemical measurements reported in this study were performed using cyclic voltammetry (CV). We evaluated the effect of pH and the presence of different concentrations of magnetic Fe3O4 nanoparticles aggregates always initially added to the aqueous phase on tetramethylammonium cation (TMA+), and 4-octylbenzenesulfonic acid (OBS-) ion transfer. We have found that the addition of Fe3O4 MPs followed by their precipitation and LLI interface modification leads to pH dependent magnification of the recorded ionic currents attributed to the cation and anion transfer from the aqueous to the organic phase and vice versa. As such, we have plotted the calibration curves of TMA+ and OBS- in the concentration range of (10-200 μM) revealing that Fe3O4 MPs have a significant effect on detection sensitivity, which is dependent on the interaction between Fe3O4 MPs and the analyte being studied. Finally, we assessed the electrochemical behavior of levamisole at the 1,2-dichloroethane|water interface in the presence and absence of Fe3O4 MPs.

Levamisole, as a viral vaccine adjuvant, induces robust host defense through the modulation of innate and adaptive immune responses

Introduction

An effective vaccination policy must be implemented to prevent foot-and-mouth disease (FMD). However, the currently used vaccines for FMD have several limitations, including induction of humoral rather than cellular immune responses.

Methods

To overcome these shortcomings, we assessed the efficacy of levamisole, a small-molecule immunomodulator, as an adjuvant for the FMD vaccine. We conducted in vitro studies using murine peritoneal exudate cells (PECs) and porcine peripheral blood mononuclear cells (PBMCs) and in vivo studies using mice (experimental animals) and pigs (target animals). We evaluated levamisole-mediated modulation of the innate and adaptive immune responses; early, mid-term, and long-term immune-inducing effects; modes of action; and host defense against viral infection.

Results

Levamisole treatment promoted IFNγ secretion in murine PECs and porcine PBMCs. Additionally, it induced robust and long-lasting immune responses by eliciting high antibody titers and high virus-neutralizing antibody titers. By activating downstream signaling pathways of various pattern-recognition receptors, levamisole stimulated the expression of multiple cytokines and costimulatory molecules. Owing to these immunostimulatory effects, levamisole elicited host defense against viral infections in pigs. Our findings demonstrate the potential of levamisole as an immunostimulatory agent.

Discussion

The results also indicate that levamisole, as an adjuvant for animal vaccines, can elicit robust innate and adaptive immune responses, thereby enhancing host defense against viral infections. This study provides a promising approach for the development of improved FMD vaccine strategies in the future.

Levamisole Ameliorates Rheumatoid Arthritis by Downregulating the PI3K/Akt Pathway in SD Rats

Background/Objectives: Rheumatoid arthritis (RA) is a systemic chronic autoimmune disease characterized by a protracted course, high rates of morbidity, and disability yet lacks effective therapeutic modalities. Levamisole (LVM), an immunomodulatory drug, has been clinically reported for its potential in RA treatment, while its therapeutic mechanism toward RA remains to be elucidated. Hence, this study provides theoretical support for the application of LVM in the treatment of RA. Methods: This study employed male Sprague-Dawley (SD) rats to construct the adjuvant-induced arthritis (AIA) model, administering LVM orally (5 mg/kg, 15 mg/kg, and 45 mg/kg) for 25 days. An evaluation of LVM's therapeutic effects on RA was conducted through arthritis index scores, paw pad thickness, paw volume, hematoxylin and eosin (H&E) staining, 3D microcomputed tomography (micro-CT) scans, serum levels of pro-/anti-inflammatory cytokines, and serum biochemical indicators. Western blotting and immunohistochemistry staining were utilized to measure the expression levels of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) proteins in synovial and ankle joint tissues. Results: Treatment with the median dose of LVM (15 mg/kg, M-LVM) significantly reduced the arthritis index (p < 0.01), paw pad thickness (p < 0.001), and paw volume (p < 0.01) without affecting body weight. Additionally, M-LVM alleviated inflammatory lesions in the synovium and ankle joints and also normalized serum levels of interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta (TGF-β). The Model group exhibited significant increases in serum levels of alkaline phosphatase (ALP) (p < 0.01), creatine kinase (CK) (p < 0.05), and glucose (GLU) (p < 0.001) compared with the Control group; however, M-LVM effectively regulated these parameters to normal levels. Western blotting and immunohistochemistry staining revealed that PI3K-/Akt-related proteins were highly expressed in the synovial and ankle joint tissues of rats in the Model group, while treatment with M-LVM significantly reduced the expression of these proteins. Furthermore, histological examination of major organs (heart, liver, lungs, kidneys, and thymus) showed no significant pathological changes, with the exception of the spleen, where M-LVM ameliorated splenic lesions. Conclusions: We demonstrate that LVM at an optimal dose substantially relieves synovitis and bone erosion in AIA rats by inhibiting the PI3K/Akt signaling pathway.

Levamisole Modulation of Podocytes' Actin Cytoskeleton in Nephrotic Syndrome

Podocytes play a central role in glomerular diseases such as (idiopathic) nephrotic syndrome (iNS). Glucocorticoids are the gold standard therapy for iNS. Nevertheless, frequent relapses are common. In children with iNS, steroid-sparing agents are used to avoid prolonged steroid use and reduce steroid toxicity. Levamisole is one of these steroid-sparing drugs and although clinical effectiveness has been demonstrated, the molecular mechanisms of how levamisole exerts its beneficial effects remains poorly studied. Apart from immunomodulatory capacities, nonimmunological effects of levamisole on podocytes have also been suggested. We aimed to elaborate on the effects of levamisole on human podocytes in iNS. RNA sequencing data from a human podocyte cell line treated with levamisole showed that levamisole modulates the expression of various genes involved in actin cytoskeleton stabilization and remodeling. Functional experiments showed that podocytes exposed to puromycin aminonucleoside (PAN), lipopolysaccharides (LPS), and NS patient plasma resulted in significant actin cytoskeleton derangement, reduced cell motility, and impaired cellular adhesion when compared to controls, effects that could be restored by levamisole. Mechanistic studies revealed that levamisole exerts its beneficial effects on podocytes by signaling through the glucocorticoid receptor and by regulating the activity of Rho GTPases. In summary, our data show that levamisole exerts beneficial effects on podocytes by stabilizing the actin cytoskeleton in a glucocorticoid receptor-dependent manner.

Immune-enhancement effects of Angelica gigas Nakai extracts via MAPK/NF-ƙB signaling pathways in cyclophosphamide-induced immunosuppressed mice

This study investigated the immune-enhancement effects of Angelica gigas Nakai extract (ANE) and its yeast-fermented extract (FAN) in cyclophosphamide (CPP)-induced immunosuppressed mice. Angelica gigas Nakai (AGN) increased the protein level of inducible nitric oxide synthase (iNOS) and the production of nitric oxide (NO) and immune-related cytokines in mouse splenocytes. AGN also restored CPP-induced suppression of NK cell activity and splenocyte proliferation. Furthermore, AGN activated the ERK and p38 MAPK/NF-κB signaling pathways in mouse splenocytes via phosphorylation of signaling molecules. These findings indicate that upregulation of cytokines and enzymes may be closely associated with the MAPK/NF-κB signaling pathways. In conclusion, AGN can restore CPP-induced immunosuppression in mice, although there was no significant difference in the immune-enhancing effect between ANE and FAN. It is suggested that AGN might have the potential to enhance immunity as an immunostimulant under immunosuppressed conditions. Therefore, it could be used as an effective agent or a dietary supplement for improving immunity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01281-6.

From Bench to Bedside: What Do We Know about Imidazothiazole Derivatives So Far?

Imidazothiazole derivatives are becoming increasingly important in therapeutic use due to their outstanding physiological activities. Recently, applying imidazothiazole as the core, researchers have synthesized a series of derivatives with biological effects such as antitumor, anti-infection, anti-inflammatory and antioxidant effects. In this review, we summarize the main pharmacological effects and pharmacological mechanisms of imidazothiazole derivates; the contents summarized herein are intended to advance the research and rational development of imidazothiazole-based drugs in the future.

Co-administration of morphine and levamisole increases death risk, produces neutropenia and modifies antinociception in mice

Levamisole is a veterinary anthelmintic drug and a common adulterant of misused drugs. This study analyses the lethal, antinociceptive and haematological effects produced by acute or repeated levamisole administration by itself or combined with morphine. Independent groups of male Swiss Webster mice were i.p. injected with 100 mg/kg morphine, 31.6 mg/kg levamisole (lethal doses at 10%, LD₁₀ ) or the same doses combined. Naloxone pretreatment (10 mg/kg, i.p.) prevented morphine-induced death, as did 2.5 mg/kg, i.p. mecamylamine with levamisole. Co-administration of levamisole and morphine (Lvm + Mor) increased lethality from 10% to 80%. This augmented effect was prevented by 30 mg/kg, i.p. naloxone and reduced with 10 mg/kg naloxone plus 2.5 mg/kg, i.p. mecamylamine. In independent groups of mice, 17.7 mg/kg, i.p. levamisole antagonized the acute morphine's antinociceptive effect evaluated in the tail-flick test. Repeated 17.7 mg/kg levamisole administration (2×/day/3 weeks) did not affect tolerance development to morphine (10 mg/kg, 3×/day/1 week). Blood samples obtained from mice repeatedly treated with levamisole showed leukopenia and neutropenia. Morphine also produced neutropenia, increased erythrocyte count and other related parameters (e.g. haemoglobin). Lvm + Mor had similar effects on leukocyte and neutrophil counts to those seen with levamisole only, but no erythrocyte-related alterations were evident. Blood chemistry analysis did not indicate liver damage but suggested some degree of electrolyte balance impairment. In conclusion, Lvm + Mor increased death risk, altered morphine-induced antinociceptive effects and produced haematologic abnormalities. The importance of studying combinations of drugs of abuse lies in the fact that drug users frequently combine drugs, which are commonly adulterated.

Immune-Enhancing Effects of Crude Polysaccharides from Korean Ginseng Berries on Spleens of Mice with Cyclophosphamide-Induced Immunosuppression

Panax ginseng C. A. Meyer is well known as traditional herbal medicine, and ginseng berries are known to exhibit potential immune-enhancing functions. However, little is known about the in vivo immunomodulatory activity of Korean ginseng berries. In this study, crude Korean ginseng berries polysaccharides (GBP) were isolated and their immunomodulatory activities were investigated using cyclophosphamide (CY)-induced immunosuppressive BALB/c mice. In CY-treated mice, oral administration of GBP (50-500 mg/kg BW) remarkably increased their spleen sizes and spleen indices and activated NK cell activities. GBP also resulted in the proliferation of splenic lymphocytes (coordinating with ConA: plant mitogen which is known to stimulate T-cell or LPS: endotoxin which binds receptor complex in B cells to promote the secretion of pro-inflammatory cytokines) in a dose-dependent manner. In addition, GBP significantly stimulated mRNA expression levels of immune-associated genes including interleukin-1β (IL-1β), IL-2, IL-4, IL-6, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), toll-like receptor 4 (TLR-4), and cyclooxygenase-2 (COX-2) in CY-treated mice. These results indicate that GBP is involved in immune effects against CY-induced immunosuppression. Thus, GBP could be developed as an immunomodulation agent for medicinal or functional food application.

Nanotechnology-based Approaches and Investigational Therapeutics against COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the novel coronavirus responsible for the current global pandemic, which first emerged in December 2019. This coronavirus has affected 217 countries worldwide, most of which have enacted non-remedial preventive measures, such as nationwide lockdowns, work from home, travel bans, and social isolation. Pharmacists, doctors, nurses, technologists, and other healthcare professionals have played pivotal roles during this pandemic. Unfortunately, confirmed drugs have not been identified for the treatment of patients with coronavirus disease 2019 (COVID-19) caused by SARSCoV2; however, favipiravir and remdesivir have been reported as promising antiviral drugs. Some vaccines have already been developed, and vaccination is ongoing globally. Various nanotechnologies are currently being developed in many countries for preventing SARS-CoV-2 spread and treating COVID-19 infections. In this article, we present an overview of the COVID-19 pandemic situation and discuss nanotechnology-based approaches and investigational therapeutics for COVID-19.

IgE-Mediated Reaction to Levamisole: Evaluation of a Patient With Severe Anaphylaxis

Levamisole has been used as adjuvant immunomodulatory therapy for certain conditions such as amyotrophic lateral sclerosis (ALS). We present a case of a 70-year-old man with ALS who was started on levamisole with adequate response. Within 10 days of treatment, he developed a maculopapular non-pruritic rash on his extremities, and the medication was discontinued. However, two days later, he developed angioedema of the face and hands, urticaria in the extremities and torso, and throat closing sensation that was successfully treated in the emergency department with epinephrine, systemic corticosteroids, and antihistamines. Eight hours later, he presented with recurrent facial angioedema. He was transferred to the ICU and received two more doses of epinephrine and intravenous methylprednisolone. The patient fully recovered within 72 hours and was discharged with the indication to avoid levamisole. One month after the reaction, skin tests (prick and intradermal) with 10-fold dilutions of 550 mg/mL levamisole were positive at a concentration of 55 mg/mL (1:10 dilution). Since the patient developed anaphylaxis and tested positive for levamisole on intradermal testing, and after discussing the options with him, we decided to advise against using this medication since the benefits did not outweigh the risks of administration. This case highlights that IgE-mediated reactions to levamisole, while rare, can occur and be life-threatening. Shared decision-making should be done between patients and physicians after open, evidence-based discussions.

Adverse reactions with levamisole vary according to its indications and misuse: a systematic pharmacovigilance study

AIM

Levamisole was initially prescribed for the treatment of intestinal worms. Because of immunomodulatory properties, levamisole has been used in inflammatory pathologies and in cancers in association with 5-fluorouracil. Levamisole is misused as a cocaine adulterant. Post-marketing reports have implicated levamisole in the occurrence of adverse drug reactions (ADRs) and its use is now limited in Europe and North America. In contrast, all other parts of the World continue to use single-dose as an anthelmintic. The aim of this study was to identify ADRs reported after levamisole exposure in VigiBase, the WHO's pharmacovigilance database, and analyze their frequency compared to other drugs and according to levamisole type of use.

METHODS

All levamisole-related ADRs were extracted from VigiBase®. Disproportionality analyses were conducted to investigate psychiatric, hepatobiliary, renal, vascular, nervous, blood, skin, cardiac, musculoskeletal and general ADRs associated with levamisole and other drugs exposure. In secondary analyses, we compared the frequency of ADRs between levamisole and mebendazole and between levamisole type of use.

RESULTS

Among the 1763 levamisole-related ADRs identified, psychiatric disorders (Reporting Odds-Ratio with 95% confidence intervals: 1.4 [1.2-2.6]), hepatobiliary disorders (2.4 [1.9-4.3]), vasculitis (6.5 [4.1-10.6]), encephalopathy (22.5 [17.4-39.9]), neuropathy (4.3 [2.9-7.1]), hematological disorders, mild rashes and musculoskeletal disorders were more frequently reported with levamisole than with other drug. The majority of levamisole-related ADRs occurred when the drug was administrated for a non-anti-infectious indication.

CONCLUSION

The great majority of the levamisole-related ADRs concerned its immunomodulatory indication and multiple doses regimen. Our results suggest that single-dose treatments for anthelmintic action have a good safety profile.

Repurposing of Antimicrobial Agents for Cancer Therapy: What Do We Know?

The substantial costs of clinical trials, the lengthy timelines of new drug discovery and development, along the high attrition rates underscore the need for alternative strategies for finding quickly suitable therapeutics agents. Given that most approved drugs possess more than one target tightly linked to other diseases, it encourages promptly testing these drugs in patients. Over the past decades, this has led to considerable attention for drug repurposing, which relies on identifying new uses for approved or investigational drugs outside the scope of the original medical indication. The known safety of approved drugs minimizes the possibility of failure for adverse toxicology, making them attractive de-risked compounds for new applications with potentially lower overall development costs and shorter development timelines. This latter case is an exciting opportunity, specifically in oncology, due to increased resistance towards the current therapies. Indeed, a large body of evidence shows that a wealth of non-cancer drugs has beneficial effects against cancer. Interestingly, 335 drugs are currently being evaluated in different clinical trials for their potential activities against various cancers (Redo database). This review aims to provide an extensive discussion about the anti-cancer activities exerted by antimicrobial agents and presents information about their mechanism(s) of action and stage of development/evaluation.

Efficacy and safety of Levamisole treatment in clinical presentations of non-hospitalized patients with COVID-19: a double-blind, randomized, controlled trial

BACKGROUND

Levamisole has shown clinical benefits in the management of COVID-19 via its immunomodulatory effect. However, the exact role of Levamisole effect in clinical status of COVID-19 patients is unknown. We aimed to evaluate the efficacy of Levamisole on clinical status of patients with COVID-19 during their course of the disease.

METHODS

This prospective, double-blind, randomized controlled clinical trial was performed in adult patients with mild to moderate COVID-19 (room-air oxygen saturation > 94%) from late April 2020 to mid-August 2020. Patients were randomly assigned to receive a 3-day course of Levamisole or placebo in combination with routine standard of care.

RESULTS

With 25 patients in each arm, 50 patients with COVID-19 were enrolled in the study. Most of the study participants were men (60%). On days 3 and 14, patients in Levamisole group had significantly better cough status distribution when compared to the placebo group (P-value = 0.034 and 0.005, respectively). Moreover, there was significant differences between the two groups in dyspnea at follow-up intervals of 7 (P-value = 0.015) and 14 (P-value = 0.010) days after receiving the interventions. However, no significant difference in fever status was observed on days 1, 3, 7, and 14 in both groups (P-value > 0.05).

CONCLUSION

The results of the current study suggest that Levamisole may improve most of clinical status of patients with COVID-19. The patients receiving Levamisole had significantly better chance of clinical status including cough and dyspnea on day 14 when compared to the placebo. However, the effect-size of this finding has uncertain clinical importance.

TRIAL REGISTRATION

The trial was registered as IRCT20190810044500N7 (19/09/2020).

Pharmacological treatments of COVID-19

The viral infection due to the new coronavirus or coronavirus disease 2019 (COVID-19), which was reported for the first time in December 2019, was named by the World Health Organization (WHO) as Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV2), because of the very similar genome and also its related symptoms to SARS-CoV1. The ongoing COVID-19 pandemic with significant mortality, morbidity, and socioeconomic impact is considered by the WHO as a global public health emergency. Since there is no specific treatment available for SARS-CoV2 infection, and or COVID-19, several clinical and sub-clinical studies are currently undertaken to find a gold-standard therapeutic regimen with high efficacy and low side effect. Based on the published scientific evidence published to date, we summarized herein the effects of different potential therapies and up-to-date clinical trials. The review is intended to help readers aware of potentially effective COVID-19 treatment and provide useful references for future studies.

COVID-19 Outbreak: Pathogenesis, Current Therapies, and Potentials for Future Management

At the end of 2019, a novel coronavirus (CoV) was found at the seafood market of Hubei province in Wuhan, China, and this virus was officially named coronavirus diseases 2019 (COVID-19) by World Health Organization (WHO). COVID-19 is mainly characterized by severe acute respiratory syndrome coronavirus-2 (SARS-CoV2) and creates public health concerns as well as significant threats to the economy around the world. Unfortunately, the pathogenesis of COVID-19 is unclear and there is no effective treatment of this newly life-threatening and devastating virus. Therefore, it is crucial to search for alternative methods that alleviate or inhibit the spread of COVID-19. In this review, we try to find out the etiology, epidemiology, symptoms as well as transmissions of this novel virus. We also summarize therapeutic interventions and suggest antiviral treatments, immune-enhancing candidates, general supplements, and CoV specific treatments that control replication and reproduction of SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV).

Potential Anti-SARS-CoV-2 Therapeutics That Target the Post-Entry Stages of the Viral Life Cycle: A Comprehensive Review

The coronavirus disease-2019 (COVID-19) pandemic continues to challenge health care systems around the world. Scientists and pharmaceutical companies have promptly responded by advancing potential therapeutics into clinical trials at an exponential rate. Initial encouraging results have been realized using remdesivir and dexamethasone. Yet, the research continues so as to identify better clinically relevant therapeutics that act either as prophylactics to prevent the infection or as treatments to limit the severity of COVID-19 and substantially decrease the mortality rate. Previously, we reviewed the potential therapeutics in clinical trials that block the early stage of the viral life cycle. In this review, we summarize potential anti-COVID-19 therapeutics that block/inhibit the post-entry stages of the viral life cycle. The review presents not only the chemical structures and mechanisms of the potential therapeutics under clinical investigation, i.e., listed in clinicaltrials.gov, but it also describes the relevant results of clinical trials. Their anti-inflammatory/immune-modulatory effects are also described. The reviewed therapeutics include small molecules, polypeptides, and monoclonal antibodies. At the molecular level, the therapeutics target viral proteins or processes that facilitate the post-entry stages of the viral infection. Frequent targets are the viral RNA-dependent RNA polymerase (RdRp) and the viral proteases such as papain-like protease (PLpro) and main protease (Mpro). Overall, we aim at presenting up-to-date details of anti-COVID-19 therapeutics so as to catalyze their potential effective use in fighting the pandemic.

Fluoropyrimidine Modulation of the Anti-Tumor Immune Response-Prospects for Improved Colorectal Cancer Treatment

Chemotherapy modulates the anti-tumor immune response and outcomes depend on the balance of favorable and unfavorable effects of drugs on anti-tumor immunity. 5-Florouracil (5-FU) is widely used in adjuvant chemotherapy regimens to treat colorectal cancer (CRC) and provides a survival benefit. However, survival remains poor for CRC patients with advanced and metastatic disease and immune checkpoint blockade therapy benefits only a sub-set of CRC patients. Here we discuss the effects of 5-FU-based chemotherapy regimens to the anti-tumor immune response. We consider how different aspects of 5-FU's multi-factorial mechanism differentially affect malignant and immune cell populations. We summarize recent studies with polymeric fluoropyrimidines (e.g., F10, CF10) that enhance DNA-directed effects and discuss how such approaches may be used to enhance the anti-tumor immune response and improve outcomes.

Potential interventions for novel coronavirus in China: A systematic review

An outbreak of a novel coronavirus (COVID‐19 or 2019‐CoV) infection has posed significant threats to international health and the economy. In the absence of treatment for this virus, there is an urgent need to find alternative methods to control the spread of disease. Here, we have conducted an online search for all treatment options related to coronavirus infections as well as some RNA‐virus infection and we have found that general treatments, coronavirus‐specific treatments, and antiviral treatments should be useful in fighting COVID‐19. We suggest that the nutritional status of each infected patient should be evaluated before the administration of general treatments and the current children's RNA‐virus vaccines including influenza vaccine should be immunized for uninfected people and health care workers. In addition, convalescent plasma should be given to COVID‐19 patients if it is available. In conclusion, we suggest that all the potential interventions be implemented to control the emerging COVID‐19 if the infection is uncontrollable.

Impact of levamisole in co-administration with benznidazole on experimental Chagas disease

Levamisole (Lms) is an anthelminthic drug with immunomodulatory activity. Chagas disease (CD) is caused by Trypanosoma cruzi and there is very low access to the drugs available, benznidazole (Bz) and nifurtimox, both far from ideal. In a drug-repurposing strategy to test potential activity as antiparasitic and immunomodulatory agent for CD, Lms was assayed on acute T. cruzi murine infection, alone and in co-administration with Bz. During protocol standardization, 100 and 10 mpk of Bz given for five consecutive days resulted in parasitaemia suppression and 100% animal survival only with the highest dose. Flow cytometry showed that both optimal (100 mpk) and suboptimal (10 mpk) doses of Bz equally decreased the plasma levels of cytokines commonly elevated in this acute infection model. Lms alone (10-0.5 mpk) did not decrease parasitaemia nor mortality rates. Co-administration was investigated using the suboptimal dose of Bz and different doses of Lms. While Bz 10 mpk did not alter parasitaemia, the combo partially reduced it but only slightly promoted animal survival. This effect could be related to Th1-response modulation since interleukin-6 and interferon-γ were higher after treatment with the combo.

Efficacy of higher-dose levamisole in maintaining remission in steroid-dependant nephrotic syndrome

OBJECTIVE

Levamisole (LEV) has been used successfully on an alternate-day regime of 2.5 mg/kg in steroid-dependant nephrotic syndrome (SDNS) to maintain remission. This pilot study was carried out between 2010 and 2015 at a single center in Sri Lanka to evaluate the efficacy of LEV prescribed at 2.5 mg/kg daily, which is double the alternate-day dose.

METHODS

Sequential children with SDNS, relapsing more than twice in the preceding 12 months and previously treated with LEV and low-dose alternate-day prednisolone (0.1-0.6 mg/kg) were recruited to the study. This group received LEV (2.5 mg/kg) daily with the same dose of alternate-day prednisolone for 1 year. Urine protein excretion was recorded by parents on a daily basis, and the presence of 3+ proteinuria on 3 consecutive days was considered a relapse. Full blood counts and liver function tests were performed every 3 months to monitor for adverse effects.

RESULTS

Sixty-four children were enrolled into the study; six were excluded due to prescription of other immunosuppressive drugs. Median age was 7.9 years; 33 were boys. The number of relapse episodes was 163 [mean per patient 2.8 ± standard deviation (SD) 0.8] in patients on alternate-day LEV and 77 (mean 1.3 ± SD 0.9) for those on daily LEV during the 12-month period of observation. The P value 0.000 (according to the Wilcoxon signed-rank test) was <0.001. No major adverse events were noted.

CONCLUSIONS

The prescription of daily LEV is effective and safe for maintaining SDNS remission.

Levamisole as an Adjuvant to Short-Course Therapy in Newly Diagnosed Pulmonary Tuberculosis Patients

BACKGROUND

The estimated incidence and prevalence of tuberculosis in India are 2.1 and 2.6 million cases respectively. Immunotherapy may shorten tuberculosis treatments and improve the immunity of individuals as well. Hence we study the efficacy of levamisole (LVM) (immunomodulator) as an adjuvant to chemotherapy of pulmonary tuberculosis patients.

MATERIALS AND METHODS

A randomized, double-blind, placebo-controlled clinical trial was conducted for 21 months in newly diagnosed sputum positive pulmonary tuberculosis patients. Patients were subjected initially to clinical examination, sputum acid-fast bacilli smear and culture, tuberculin skin test and weight record. During follow-up, above investigations were repeated. Sixty-five patients were randomly assigned into two groups to receive either tab LVM 100 mg once in a day or matching placebo, orally as a single dose, thrice a week, for 2 months with short-course antituberculosis chemotherapy.

RESULTS

Sputum negativity at 1 week was observed in 11 (44%) patients in LVM group whereas only 3 (12%) in placebo group. All the patients 25 (100%) in LVM group were sputum negative compared to 14 (56%) in placebo group by the end of 3 weeks. In LVM group, 24 (96%) and 11 (44%) patients in placebo group show radiological improvement at 2 months. A direct correlation existed between quantum of immune response and weight gain with LVM. LVM rendered all anergic patients to positive tuberculin reactors. In LVM group, patients with initial Mantoux ≥20 mm and advanced cavitary disease, there was decrease in tuberculin reaction size.

CONCLUSION

Adjuvant immunomodulation with levamisole has the potential of shortening the total duration of antitubercular therapy.

Levamisole therapy in children with frequently relapsing and steroid-dependent nephrotic syndrome: a single-center experience

Introduction

Numerous studies suggest that levamisole, an antihelmintic agent with an immunomodulatory effect, reduces the number of relapses in children with frequently relapsing and steroid-dependent nephrotic syndrome (FRNS/SDNS). The aim of the study was to present a single center’s experience in treatment of FRNS and SDNS with levamisole.

Material and methods

Among 72 children with FRNS/SDNS treated in our department with levamisole in the years 1984-2011 we studied in detail 53 patients (mean age: 6.5 ±3.0 years), in whom the medication was administered for at least 6 months. In these 53 patients we evaluated: the course of the disease before levamisole, the renal biopsy result, medications used, prednisone dose on levamisole initiation, duration of levamisole treatment, time to first relapse and number of relapses on levamisole, and levamisole side effects.

Results

The duration of nephrotic syndrome was 3.4 ±2.9 years, and the number of relapses before levamisole treatment was 6.0 ±3.4. The dose of prednisone on initiation of levamisole treatment was 1.2 ±0.6 mg/kg/24 h, and the duration of levamisole treatment was 15.0 ±7.3 months. During levamisole treatment proteinuria relapsed in 34/53 (64.2%) children, and the time to first relapse was 8.8 ±8.1 months. During levamisole therapy relapses of the disease decreased significantly (2.7 ±2.0 vs. 1.8 ±2.1 relapses/year, p = 0.02). Time to first relapse correlated with total number of relapses (R = –0.59, p < 0.001) and number of relapses in one year during levamisole treatment (R = –0.60, p < 0.001).

Conclusions

Levamisole is effective in reducing the number of relapses in children with frequently relapsing and steroid-dependent nephrotic syndrome. Early relapse of proteinuria on levamisole treatment in children with FRNS/SDNS suggests low efficacy of further treatment.

Levamisole Activates Several Innate Immune Factors in Scophthalmus Maximus (L.) (Teleostei)

Levamisole, originally synthesized as an anti-helminthic, has been widely used in human and veterinary medicine as an immunomodulator or adjuvant. However, data on its use in fish are scarce, and no information is available for turbot. To study the effects of levamisole treatment on the innate immune system of juvenile turbot, two different doses (D1=500 mg/kg; D2=250 mg/kg dry food) were orally administered for 2 weeks and samplings were performed at −10, 14, 28, 49 and 77 days post treatment (p.t.). Biometrical, haematological, histological and immunological data were obtained. Specific growth rate was higher in the medicated groups than in the control (C), but the difference was statistically significant only for D1 fish at day 49 p.t. The leucocytes/trombocytes ratio was significantly higher in D1 than in C fish at 14 days p.t., but decreased subsequently. At most samplings, the percentage of the circulating lymphocytes was lower and that of the progranulocytes was higher in the medicated fish than in the C ones. The percentage offish with high haemotopoietic activity in the kidney was clearly higher in D1 and D2 fish than in C ones at some sampling points. The respiratory burst activity of blood leucocytes was significantly higher in D1 fish than in C ones in all samplings, except at day 77 p.t. when control fish experienced a rebound effect. In all medicated fish, an initial increase of such activity was observed, followed by a further decrease. Their serum peroxidases followed a contrary pattern, with a decrease in the second sampling and a subsequent and non-significant recovery, a situation also observed for serum lysozyme and complement. Therefore, oral levamisole treatment actually affects some turbot immune factors, although stimulation or depression can occur depending on the considered factor and the administered dose. These results point out the interest of further studies on the mechanisms involved in the levamisole action for its adequate use as immunomodulator.

A review of the evolution of systemic chemotherapy in the management of colorectal cancer

Herein we present a historical review of the development of systemic chemotherapy for colorectal cancer (CRC) in the metastatic and adjuvant treatment settings. We describe the discovery of 5-fluorouracil (5-FU) by Heidelberger and colleagues in 1957, the potentiation of 5-FU cytotoxicity by the reduced folate leucovorin, and the advent of novel cytotoxic agents, including the topoisomerase I inhibitor irinotecan, the platinum-containing agent oxaliplatin, and the 5-FU prodrug capecitabine. The combination therapies, FOLFOX (5-FU/leucovorin and oxaliplatin) and FOLFIRI (5-FU/leucovorin and irinotecan), have become established as efficacious cytotoxic regimens for the treatment of metastatic CRC, resulting in overall survival times of approximately 2 years. When used as adjuvant therapy, FOLFOX also improves survival and is now the gold standard of care in this setting. Biological agents have been discovered that enhance the effect of cytotoxic therapy, including bevacizumab (a humanized monoclonal antibody that targets vascular endothelial growth factor, a central regulator of angiogenesis) and cetuximab/panitumumab (monoclonal antibodies directed against the epidermal growth factor receptor). Despite the ongoing development of novel antitumor agents and therapeutic principles as we enter the era of personalized cancer medicine, systemic chemotherapy involving infusional 5-FU/leucovorin continues to be the cornerstone of treatment for patients with CRC.

Can immunostimulants efficiently replace antibiotic in striped catfish (Pangasianodon hypophthalmus) against bacterial infection by Edwardsiella ictaluri?

The present study was performed to determine the efficacy of lipopolysaccharide (LPS) and levamisole on immune response and disease resistance in striped catfish and to compare their respective efficiency with the one of an antibiotic treatment after infection of fish by the bacteria Edwardsiella ictaluri. Fish were divided into 3 groups and each group was injected with LPS (3 mg/kg fish), levamisole (5 mg/kg fish) or phosphate buffer saline as control. At day 21st post immunostimulant injection, fish were bled for assaying immunological variables and then challenged with E. ictaluri. Three days after bacterial infection, an antibiotic treatment was applied into fish subgroups and mortality was compared daily between antibiotic treated and untreated fish until 2 weeks post-challenge. LPS and levamisole significantly enhanced non-specific immune responses such as respiratory burst, lysozyme and complement activity in fish compared with control (p < 0.05). Respiratory burst and complement activity significantly increased in levamisole groups when compared with LPS groups while lysozyme activity did not differ significantly between immunostimulant treatments. Total immunoglobulins significantly increased in levamisole treatment compared with control. After challenge test, accumulated mortality was reduced significantly in both non-antibiotic and antibiotic subgroups of LPS and levamisole compared with control. Moreover, no differences of mortality were observed between fish treated with levamisole or LPS without antibiotics and control fish treated with antibiotics. These results support the possible replacement of antibiotics in striped catfish farming by immunostimulants such as levamisole and LPS.

Present-day anthelmintics and perspectives on future new targets

In absence of vaccines for the majority of helminths, chemotherapy is still the mainstay for controlling human helminthiases. However, a limited number of drugs are available in the market to combat parasitic helminths in human. Besides, the development and spread of drug resistance have declined the use of most currently available anthelmintics. Clearly, availability of new anthelmintic agents will be essential in the next few years. More research into the mechanisms of drug actions and their targets are eminent for the discovery and development of novel anthelmintic agents. Recent drug discovery techniques mostly rely on mechanism-based screening of compounds on heterologously expressed targets in bacterial, mammalian or yeast cells. Although this is usually a successful approach, it is money- and time-consuming; meanwhile, pharmaceutical companies prefer the tested target that is chosen based on basic research. The nervous system is the site of action of several chemotherapeutics including pesticides and antinematode drugs; accordingly, the nervous system continues to be a promising target. Recent advances in exploring helminths' nervous system, neurotransmitters and receptors have paved the way for the development of potential agents targeting the nervous system and its components.

Aminorex, a metabolite of the cocaine adulterant levamisole, exerts amphetamine like actions at monoamine transporters

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We quantified adulterants in street drugs sold as cocaine.

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We analyzed effects of the most common adulterant levamisole, on neurotransmitter transporters.

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Differences in the selectivity of levamisole can be explained by homology modelling and docking.

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Aminorex, a metabolite of levamisole, modulates neurotransmitter transporters directly.

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Depending on the transporter, aminorex acts as a blocker or as a releaser.

Psychostimulants such as amphetamine and cocaine are illicitly used drugs that act on neurotransmitter transporters for dopamine, serotonin or norepinephrine. These drugs can by themselves already cause severe neurotoxicity. However, an additional health threat arises from adulterant substances which are added to the illicit compound without declaration. One of the most frequently added adulterants in street drugs sold as cocaine is the anthelmintic drug levamisole. We tested the effects of levamisole on neurotransmitter transporters heterologously expressed in HEK293 cells. Levamisole was 100 and 300-fold less potent than cocaine in blocking norepinephrine and dopamine uptake, and had only very low affinity for the serotonin transporter. In addition, levamisole did not trigger any appreciable substrate efflux. Because levamisole and cocaine are frequently co-administered, we searched for possible allosteric effects; at 30 μM, a concentration at which levamisole displayed already mild effects on norepinephrine transport it did not enhance the inhibitory action of cocaine. Levamisole is metabolized to aminorex, a formerly marketed anorectic drug, which is classified as an amphetamine-like substance. We examined the uptake-inhibitory and efflux-eliciting properties of aminorex and found it to exert strong effects on all three neurotransmitter transporters in a manner similar to amphetamine. We therefore conclude that while the adulterant levamisole itself has only moderate effects on neurotransmitter transporters, its metabolite aminorex may exert distinct psychostimulant effects by itself. Given that the half-time of levamisole and aminorex exceeds that of cocaine, it may be safe to conclude that after the cocaine effect “fades out” the levamisole/aminorex effect “kicks in”.

Levamisole usage as an adjuvant to hepatitis B vaccine in hemodialysis patients, yes or no?

BACKGROUND

Hepatitis B virus (HBV) infection is much more common in hemodialysis patients than the general population. These patients have an impaired immune response to HBV vaccination; to that end there are certain studies that have evaluated levamisole as an immunomodulator agent improving HBV vaccination response rate in hemodialysis patients.

OBJECTIVES

In the current review, we have assembled all of the results to determine whether lavamisole is of value as an adjuvant to HBV vaccination in hemodialysis patients.

MATERIALS AND METHODS

Science Direct (Elsevier), ProQuest, Springer, MD Consult, BMJ Journals, Pubmed and Wiley were searched for levamisole application to HBV vaccination in hemodialysis patients. All studies revealed a seroconversion response level between levamisole plus HBV vaccine versus HBV vaccine alone.

RESULTS

From 10 relevant studies, 5 studies fulfilled our inclusion criteria. Three of them suggested the significant benefit of adding levamisole to the HBV vaccine to increase augment seroprotection level in hemodialysis patients. Another study reported a decrease in seroprotection level and another study showed no significant difference caused by levamisole administration.

CONCLUSIONS

Due to the limited number of studies evaluated, it is challenging to perform a definite decision about routinely administering levamisole in addition to the HBV vaccine for all hemodialysis patients. However, it does seem reasonable to recommend administration of levamisole for impaired immune response patients.

Biochemical, immunomodulatory and antioxidant properties of levamisole at different storage conditions and administration routes

Levamisole is a broad-spectrum nicotinic anthelmintic drug; widely used in veterinary medicine. Levamisole actions are variable depending on storage temperature and administration route. The present study was conducted to test levamisole effects on immune responses and antioxidant status of rats at different storage temperature and administration routs. The experimental rats were allocated into four experimental groups and two controls. Group 1 was given levamisole orally. Group 2 was injected levamisole intramuscularly. In group 1 and 2 levamisole was stored at 4 degrees C for 72 h and given every two days for three weeks at a dose of 2.5 mg kg(-1) body weight. Group 3 and 4 were treated same as group 1 and 2 but levamisole was stored at 37 degrees C. Serum levels of total IgG and IgA and plasma levels of glutathione reductase (GSSG-R), TAC concentrations in addition to GST and GSH-Px activities were measured. The results indicated that the storage of levamisole at 4 degrees C significantly increased serum IgG and IgA levels in rats and improved rat's antioxidant status through significant increase in glutathione related enzymes (GSSG-R, GST and GSH-Px) and the TAC. Levamisole stored at 37 degrees C increased measured antioxidant biomarkers but decreased the rats' non-specific humoral immunity. Moreover, the intramuscular administration induced better antioxidant properties than oral administration of levamisole. In conclusion, levamisole actions could be specifically directed towards certain types of immune responses due to changes in storage temperature with better response to injectable routes than oral routs with more antioxidant activities.

Effect of levamisole on the immune response of patients with schistosomiasis after treatment with praziquantel

Successful therapy with praziquantel in schistosomiasis is dependent on a normal host immune system, i.e. the recognition of parasite antigen, to be effective in eradicating the parasite. Levamisole, a nonspecific immunomodulator, has been hypothesised to normalise deficient cell-mediated immunity. The aim of this study was to investigate the effect of levamisole on the immune response seen after presumed curative doses of praziquantel. After ethical approval, 29 male volunteers infected with Schistosoma haematobium were recruited and randomised to receive orally either (a) levamisole 5 mg/kg for 2 consecutive days, plus praziquantel 40 mg/kg as a single dose, (b) levamisole 5 mg/kg for 2 days, or (c) praziquantel 40 mg/kg as a single dose. Blood samples were collected on day 0 and again 3 months later for differential counts and specific IgG and IgE to whole-worm-antigen, as well as for the detection of eosinophil cationic protein (ECP). Levamisole treatment alone resulted in a significant drop in circulating eosinophil counts, i.e. a median (95% confidence interval) drop of 6.0 (1;7)%. Eosinophil counts did not change significantly after praziquantel therapy alone. ECP values were significantly reduced with levamisole alone and praziquantel alone, i.e. respective median (95% confidence interval) drops of 33.58 (18.94; 55.9) and 16.54 (3.6; 33.5) microg/L (p < 0.05). The group receiving combination therapy demonstrated significant increases in specific IgG values (p = 0.02) with no decline in ECP levels and eosinophil counts compared with baseline values. Levamisole alone had no effect on egg counts. In conclusion, levamisole inhibited circulating eosinophils and eosinophil activation when given alone, but caused immune stimulation when combined with praziquantel. The exact mechanism of action still needs to be determined.

The effects of levamisole on oxidative stress induced by copper intoxication in broilers

AIM

To determine the effects of Cu and levamisole on concentrations of Cu and Fe in plasma and liver, and the effects of levamisole on lipid peroxidation induced by Cu intoxication in broiler chickens.

METHODS

In a 2×4 factorial study, 80 one-day-old Ross PM3 broiler chicks were fed diets for 21 days containing either 8 mg/kg Cu (Low Cu) or 250 mg/kg Cu (High Cu) and were treated with 0 (L0), 4 (L4), 8 (L8) or 16 (L16) mg/kg bodyweight levamisole per day from Day 7 of the study, on three consecutive days in their drinking water. This treatment was repeated three times, at 3-day intervals. On Day 21, blood samples were collected from each bird for analysis of concentrations of Cu, Fe and malondialdehyde, and activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), superoxide dismutase, catalase and glutathione peroxidase (GSH-Px). The birds were killed and liver samples collected for analysis of Cu and Fe.

RESULTS

Mean concentrations of Cu and Fe in plasma, and Cu in liver, were increased overall in the High Cu groups compared with the Low Cu groups (p<0.001). Compared with the L0 treatment group on the High Cu diet, treatments L4, L8 and L16 decreased concentrations of Cu in plasma, and L8 and L16 increased concentration of Cu in liver (p<0.05). Mean activities of AST and ALT were increased in untreated birds (L0) fed the High compared with Low Cu diets (p<0.01). In birds receiving the High Cu diet, treatments L4 and L8 decreased activities of AST, and L4 and L16 decreased activity of ALT, compared with L0 (p<0.05). The High Cu diet induced an oxidative stress characterised by increased mean concentrations of malondialdehyde and decreased activities of superoxide dismutase, catalase and GSH-Px (p<0.001). Concentration of malondialdehyde, and activities of superoxide dismutase and catalase were not changed following levamisole treatment in birds on the High Cu diet, and activity of GSH-Px was decreased by the L4 and L8 treatments compared with the L0 group.

CONCLUSIONS AND CLINICAL RELEVANCE

The results of the study suggest that treatment with levamisole might alleviate the harmful effects of Cu on the liver, as demonstrated by decreased activities of AST and ALT induced by a diet containing 250 mg/kg Cu.

Levamisole exposure and hematologic indices in cocaine users

OBJECTIVES

Levamisole is an antihelminthic agent found in nearly 70% of seized U.S. cocaine. Sporadic case literature describes a life-threatening agranulocytosis associated with levamisole exposure secondary to cocaine use. The authors compared the distribution of hematologic indices in a population of cocaine users with and without a confirmed exposure to levamisole.

METHODS

The records of all patients in the Lifespan hospital system who underwent comprehensive toxicologic testing between September 2009 and December 2009 (n = 799) were reviewed. Of these, 95 patients were eligible for inclusion (cocaine-positive with a simultaneous complete blood count). Patients were grouped into levamisole-positive (n = 47) and -negative (n = 48) groups. The primary outcome measures were total white blood cell count (WBC), absolute neutrophil count (ANC), and absolute lymphocyte count (ALC); secondary outcome measures included percent neutrophils, lymphocytes, eosinophils, monocytes, and basophils, as well as identified co-ingestants.

RESULTS

Both groups had a similar makeup of age, sex, and race. The total WBC count, ANC, and ALC were not significantly different between the two groups. There was no significant difference in relative proportion of neutrophils, eosinophils, basophils, or monocytes between the groups. There was one neutropenic patient in the levamisole-positive group, while three patients were neutropenic in the negative group. Additionally, a literature review of case reports describing levamisole-induced agranulocytosis (n = 33) was conducted. In 52% of these cases, patients presented with an oropharyngeal chief complaint; in an additional 27%, patients presented with soft tissue infections or purpura.

CONCLUSIONS

The overall incidence of neutropenia was 4.2% in all cocaine users and 2.1% in the levamisole-positive group. A striking number of the reported patients with levamisole-associated neutropenia have presented to care with oropharyngeal complaints, vasculitis, or fever. A clinical algorithm for identifying levamisole toxicity in the emergency department setting is provided. Further research is necessary to determine the circumstances required for levamisole-associated neutropenia.

Enhancing effects of the chemical adjuvant levamisole on the DNA vaccine pVIR-P12A-IL18-3C

DNA-based vaccination is an attractive alternative for overcoming the disadvantages of inactivated virus vaccines; however, DNA vaccines alone often generate only weak immune responses. In this study, the efficacy of LMS as a chemical adjuvant on a DNA vaccine (pVIR-P12A-IL18-3C) encoding the P1-2A and 3C genes of the FMDV and swine IL-18, which provides protection against FMDV challenge, was tested. All test pigs were administered booster vaccinations 28 days after the initial inoculation, and were challenged with 1000 ID50 FMDV O/NY00 20 days after the booster vaccination. Positive and negative control groups were inoculated with inactivated virus vaccine and PBS respectively. The DNA vaccine plus LMS induced greater humoral and cell-mediated responses than the DNA vaccine alone, as evidenced by higher concentrations of neutralizing and specific anti-FMDV antibodies, and by higher concentrations of T-lymphocyte proliferation and IFN-y production, respectively. FMDV challenge revealed that the DNA vaccine plus LMS provided higher protection than the DNA vaccine alone. This study demonstrates that LMS may be useful as an adjuvant for improving the protective efficiency of DNA vaccination against FMDV in pigs.

Effect of levamisole supplementation on hepatitis B virus vaccination response in hemodialysis patients

AIM

As an immune-modulating agent, levamisole has been reported to stimulate depressed T-cell activity, enhance B lymphocyte function and restore delayed hypersensitivity reactions in immune-depressed patients. There are a number of recent studies claiming that levamisole can improve response rate to hepatitis B virus (HBV) vaccination in haemodialysis patients. The present study has examined this hypothesis amongst some Iranian patients, using double-blind randomized clinical trial.

METHODS

During a 12 month period, 70 patients on maintenance haemodialysis with negative anti-hepatitis B surface antibody (HBsAb) and HBV core antibody (HBcAb), from four different dialysis centres were enrolled into the study. The patients were randomized to two groups. The first group (levamisole group) received 40 microg doses of recombinant HBV vaccine i.m. at 0, 1 and 6 months, plus 100 mg levamisole p.o., after each haemodialysis session. The second group (placebo group) received the same vaccination protocol, except for the placebo instead of levamisole. The patients were followed on serum HBsAb level. Those with an HBsAb level of above 10 mIU/mL, 1 month after the third dose of vaccination, were considered as responders.

RESULTS

The levamisole group was comprised of 38 patients and the placebo group of 32 patients. Thirty-one patients (81.6%) of levamisole group and 26 patients (81.3%) of placebo group responded to vaccination. The difference between two groups was not significant.

CONCLUSION

This study indicated that in a haemodialysis population with high response to HBV vaccination, levamisole might have no significant effect in enhancing the response. Further studies with higher power can give more accurate results.

Upregulation of alkaline phosphatase and pyrophosphate hydrolysis: potential mechanism for uremic vascular calcification

Pyrophosphate is a potent inhibitor of medial vascular calcification where its level is controlled by hydrolysis via a tissue-nonspecific alkaline phosphatase (TNAP). We sought to determine if increased TNAP activity could explain the pyrophosphate deficiency and vascular calcification seen in renal failure. TNAP activity increased twofold in intact aortas and in aortic homogenates from rats made uremic by feeding adenine or by 5/6 nephrectomy. Immunoblotting showed an increase in protein abundance but there was no increase in TNAP mRNA assessed by quantitative polymerase chain reaction. Hydrolysis of pyrophosphate by rat aortic rings was inhibited about half by the nonspecific alkaline phosphatase inhibitor levamisole and was reduced about half in aortas from mice lacking TNAP. Hydrolysis was increased in aortic rings from uremic rats and all of this increase was inhibited by levamisole. An increase in TNAP activity and pyrophosphate hydrolysis also occurred when aortic rings from normal rats were incubated with uremic rat plasma. These results suggest that a circulating factor causes pyrophosphate deficiency by regulating TNAP activity and that vascular calcification in renal failure may result from the action of this factor. If proven by future studies, this mechanism will identify alkaline phosphatase as a potential therapeutic target.

Levamizole enhances immune responsiveness to intra-dermal and intra-muscular hepatitis B vaccination in chronic hemodialysis patients

Background

Hemodialysis patient are at high risk for hepatitis B virus (HBV) infection.

Although preventive vaccination is done routinely, the response to vaccination is low in this patient population. The aim of this study was to evaluate the effect of Levamizol, an enhancer of the immune responsiveness, on different routs of vaccination, i.e., intradermal (ID) versus intramuscular (IM), in stable chronic hemodialysis patients.

Materials and methods

Forty four chronic heamodialyses patient were divided into four equal groups. The first group was received 40 μg HB vaccine intramuscularly. The second group was received 20 μg HB vaccine intradermally. The third and the fourth group received 20 μg vaccine IM or ID, respectively, in three doses plus oral Levamisole (100 mg for 12 day). After one and six months from the last dose of vaccine, HBs antibody titers were measured.

Results

The response rate to vaccine (HBs Antibody>10 μg/L) in the routine IM HB vaccination was low (60%). It increased to 70% with ID route. Levamisole significantly raised the response rate to 90% (P < 0.01). Also in the Levamisole groups protective HB antibody titers were maintained until the end of six months.

We conclude that HD patients must be vaccinated by ID route and addition of Levamisole. Levamisole also increases antibody maintenance.

The adjuvant effect of levamisole on killed viral vaccines

To explore adjuvants that are capable of promoting Th1-biased immune response, we investigated the usefulness of levamisole (LMS) as one such adjuvant for two different preparations of killed viral vaccines, derived from the foot mouth disease virus (FMDV) or the porcine respiratory reproductive syndrome virus (PRRSV) and tested respectively in BALB/c or C57 BL/6 mice. The results showed that LMS induced different types of immune responses in the host, depending on its dosage. While a high level of serum IgG was induced by using LMS at 2%, the most robust T cell proliferation was induced with LMS at 0.5%. The Th1 and Th2 cytokine profiles, which tracked well with the antibody and T cell responses, were similarly influenced by the dose of LMS. Moreover, the enhanced T cell response correlated with increased expression of MHC and co-stimulatory molecules and decreased expression of the suppressors of cytokine signaling molecules (SOCS1 and SOCS3) in the spleen, suggesting that it is mediated by the antigen presentation, co-stimulator signaling, and cytokine production pathways. These results establish that LMS can be used to induce Th1-biased immune responses when combined with killed-virus-based antiviral vaccines and that such adjuvant effect depends on the optimal LMS dosage.