Administration In Mouse Model Research Articles

8394 Increased alpha cells mass in surrounding pancreatic islet in insulinoma patients

Abstract Disclosure: B. Kim: None. H. Park: None. J. Shin: None. K. Kim: None. Background: Insulin is an essential treatment for controlling blood sugar in diabetic patients. However, research on the direct or indirect effects of hyperinsulinemic states on pancreatic islets cell population is limited. We need to determine the morphology of surrounding pancreatic islets in insulinoma patients and changes in the pancreatic islet after insulin administration in mice model. Methods: Insulinoma and pancreatic tissue surrounding the insulinoma were obtained after surgery of a patient diagnosed with insulinoma due to frequent hypoglycemia. For mouse model, we administered short acting insulin for 7 days to 50% pancreatectomized mice, and then removed remnant pancreatic tissue. We performed insulin and glucagon immunofluorescent staining of the patient's insulinoma and surrounding pancreatic tissue and the mouse's pancreatic tissue. Results: In the insulinoma patients, persistent hyperinsulinemia and hypoglycemia was observed in prolonged fasting test. Alpha cells mass was increased in the surrounding pancreatic islets in insulinoma. Also, in the islets of insulin-treated mice, the number of alpha cells were increased, and the number of cells co-stained for both insulin and glucagon increased, and proliferation of alpha cells was observed. Conclusion: Although more research is needed to confirm the mechanism of effects of hyperinsulinemia on the proliferation of alpha cells, hyperinsulinemia is thought to play a role in the stimulation of increasing alpha cell mass and contributing to hyperglucagonemia in early diabetes. Presentation: 6/2/2024

Dynamic tracking of human umbilical cord mesenchymal stem cells (hUC-MSCs) following intravenous administration in mice model

IntroductionIn the past decades, human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have sparked interest in cellular therapy due to their immunomodulatory properties. Nevertheless, the fate of hUC-MSCs in the body remains poorly understood. This study aimed to investigate the biodistribution, homing and clearance of systemically administered hUC-MSCs in healthy BALB/c mice model. MethodshUC-MSCs were labelled with GFP-Luc2 protein, followed by characterisation with flow cytometry. Upon intravenous infusion of transduced hUC-MSCs into the healthy BALB/c mice, the cells were dynamically monitored through the bioluminescent imaging (BLI) approach. ResultsTransduction of hUC-MSCs with GFP-Luc2 not only preserved the characteristics of MSCs, but also allowed live monitoring of transduced cells in the mice model. Upon systemic administration, BLI showed that transduced hUC-MSCs first localised predominantly in the lungs of healthy BALB/c mice and mainly remained in the lungs for up to 3 days before eventually cleared from the body. At terminal sacrifice, plasma chemistry biomarkers remained unchanged except for C-peptide levels, which were significantly reduced in the hUC-MSCs group. Histopathological findings further revealed that hUC-MSCs infusion did not cause any adverse effects and toxicity to lung, liver and heart tissues. ConclusionsCollectively, systemically administrated hUC-MSCs was safe and demonstrated dynamic homing capacity before eventually disappearing from the body.

The Role of Metabotropic Glutamate Receptor Subtype 5 in Mouse Models of Cocaine Addiction

Cocaine is a psychostimulant that is one of the most widely used illicit drugs, particularly in America. Cocaine addiction is a chronic relapsing disease that is characterized by drug craving and loss of inhibitory control. Animal models of psychiatric diseases are essential to identify underlying neural circuitry and to test the effectiveness of novel pharmacotherapies to prevent relapse. Current research using animal models indicates that type 5 metabotropic glutamate receptors may be of particular importance to the onset and maintenance of cocaine addiction. This literature review provides a general overview of the glutamate system, and the animal models frequently used in the study of addiction and summarizes peer-reviewed research focused on cocaine-induced adaptations to the type 5 metabotropic glutamate receptors in mice. Cocaine administration in mouse models induces a range of neural changes in the brain, reflecting the neuroadaptations associated with cocaine addiction. Cocaine-induced adaptations to type 5 metabotropic glutamate receptor vary by brain region and by methodological constraints. Key neural changes that occur in the mouse brain following cocaine administration include adaptations in the dopaminergic and glutamatergic systems. The interplay between mGluR5 and the dopamine system plays a significant role in the neurobiological adaptations that drive cocaine addiction. Lastly, we cover the potential efficacy of targeting this receptor as a novel therapeutic option to prevent cocaine relapse. Selective antagonists of this receptor have been studied for their potential therapeutic effects in mouse models of cocaine addiction. These compounds reduce the conditioned responses to drug-associated cues and reduce the motivation to seek cocaine, thereby inhibiting relapse-like behavior, and have been found to modulate synaptic plasticity in brain regions involved in addiction, such as the nucleus accumbens and prefrontal cortex. Overall, these compounds demonstrate promising effects in mouse models of cocaine addiction.

Development of a Minimalistic Physiologically Based Pharmacokinetic (mPBPK) Model for the Preclinical Development of Spectinamide Antibiotics.

Spectinamides 1599 and 1810 are lead spectinamide compounds currently under preclinical development to treat multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis. These compounds have previously been tested at various combinations of dose level, dosing frequency, and route of administration in mouse models of Mycobacterium tuberculosis (Mtb) infection and in healthy animals. Physiologically based pharmacokinetic (PBPK) modeling allows the prediction of the pharmacokinetics of candidate drugs in organs/tissues of interest and extrapolation of their disposition across different species. Here, we have built, qualified, and refined a minimalistic PBPK model that can describe and predict the pharmacokinetics of spectinamides in various tissues, especially those relevant to Mtb infection. The model was expanded and qualified for multiple dose levels, dosing regimens, routes of administration, and various species. The model predictions in mice (healthy and infected) and rats were in reasonable agreement with experimental data, and all predicted AUCs in plasma and tissues met the two-fold acceptance criteria relative to observations. To further explore the distribution of spectinamide 1599 within granuloma substructures as encountered in tuberculosis, we utilized the Simcyp granuloma model combined with model predictions in our PBPK model. Simulation results suggest substantial exposure in all lesion substructures, with particularly high exposure in the rim area and macrophages. The developed model may be leveraged as an effective tool in identifying optimal dose levels and dosing regimens of spectinamides for further preclinical and clinical development.

Antibody-oligonucleotide conjugate achieves CNS delivery in animal models for spinal muscular atrophy.

Antisense oligonucleotides (ASOs) have emerged as one of the most innovative new genetic drug modalities. However, their high molecular weight limits their bioavailability for otherwise-treatable neurological disorders. We investigated conjugation of ASOs to an antibody against the murine transferrin receptor, 8D3130, and evaluated it via systemic administration in mouse models of the neurodegenerative disease spinal muscular atrophy (SMA). SMA, like several other neurological and neuromuscular diseases, is treatable with single-stranded ASOs that modulate splicing of the survival motor neuron 2 (SMN2) gene. Administration of 8D3130-ASO conjugate resulted in elevated levels of bioavailability to the brain. Additionally, 8D3130-ASO yielded therapeutic levels of SMN2 splicing in the central nervous system of adult human SMN2-transgenic (hSMN2-transgenic) mice, which resulted in extended survival of a severely affected SMA mouse model. Systemic delivery of nucleic acid therapies with brain-targeting antibodies offers powerful translational potential for future treatments of neuromuscular and neurodegenerative diseases.

Increased Expression and Activity of Brain Cortical cPLA2 Due to Chronic Lipopolysaccharide Administration in Mouse Model of Familial Alzheimer's Disease.

Cytosolic phospholipase A2 (cPLA2) is an enzyme regulating membrane phospholipid homeostasis and the release of arachidonic acid utilized in inflammatory responses. It represents an attractive target for the treatment of Alzheimer's disease (AD). Previously, we showed that lipopolysaccharide (LPS)-induced systemic inflammation caused abnormal lipid metabolism in the brain of a transgenic AD mouse model (APdE9), which might be associated with potential changes in cPLA2 activity. Here, we investigated changes in cPLA2 expression and activity, as well as the molecular mechanisms underlying these alterations due to chronic LPS administration in the cerebral cortex of female APdE9 mice as compared to saline- and LPS-treated female wild-type mice and saline-treated APdE9 mice. The study revealed the significant effects of genotype LPS treatment on cortical cPLA2 protein expression and activity in APdE9 mice. LPS treatment resulted in nuclear factor kappa-light-chain-enhancer of activated B cells (NFkB) activation in the cortex of APdE9 mice. The gene expressions of inflammation markers Il1b and Tnfa were significantly elevated in the cortex of both APdE9 groups compared to the wild-type groups. The study provides evidence of the elevated expression and activity of cPLA2 in the brain cortex of APdE9 mice after chronic LPS treatment, which could be associated with NFkB activation.

Comparison of pharmacokinetics and biodistribution of laser-synthesized plasmonic Au and TiN nanoparticles

Plasmonic nanostructures offer wide range of diagnostic and therapeutic functionalities for biomedical applications. Gold nanoparticles (Au NPs) present one of the most explored nanomaterial in this field, while titanium nitride nanoparticles (TiN NPs) is a new promising nanomaterial with superior plasmonic properties for biomedicine. However conventional chemical techniques for the synthesis of these nanomaterials cannot always match stringent requirements for toxicity levels and surface conditioning. Laser-synthesized Au and TiN NPs offer exceptional purity (no contamination by by-products or ligands) and unusual surface chemistry. Therefore, these NPs present a viable alternative to chemically synthesized counterparts. This work presents comparative analysis of pharmacokinetics and biodistribution of laser-synthesized 20 nm Au and TiN NPs under intravenous administration in mice model. Our data show that Au NPs and bare TiN NPs are rapidly eliminated from the blood circulation and accumulate preferentially in liver and spleen, while coating of TiN NPs by hydrophilic polymer polyethylene glycol (PEG) significantly prolongates blood circulation time and improves delivery of the NPs to tumor. We finally discuss potential applications of laser synthesized Au NPs in SERS, SEIRA and electrocatalysis, while TiN nanoparticles are considered as promising agents for photothermal therapy and photoacoustic imaging.

Antinociceptive Efficacy of the µ-Opioid/Nociceptin Peptide-Based Hybrid KGNOP1 in Inflammatory Pain without Rewarding Effects in Mice: An Experimental Assessment and Molecular Docking.

Opioids are the most effective analgesics, with most clinically available opioids being agonists to the µ-opioid receptor (MOR). The MOR is also responsible for their unwanted effects, including reward and opioid misuse leading to the current public health crisis. The imperative need for safer, non-addictive pain therapies drives the search for novel leads and new treatment strategies. In this study, the recently discovered MOR/nociceptin (NOP) receptor peptide hybrid KGNOP1 (H-Dmt-D-Arg-Aba-β-Ala-Arg-Tyr-Tyr-Arg-Ile-Lys-NH2) was evaluated following subcutaneous administration in mouse models of acute (formalin test) and chronic inflammatory pain (Complete Freund’s adjuvant-induced paw hyperalgesia), liabilities of spontaneous locomotion, conditioned place preference, and the withdrawal syndrome. KGNOP1 demonstrated dose-dependent antinociceptive effects in the formalin test, and efficacy in attenuating thermal hyperalgesia with prolonged duration of action. Antinociceptive effects of KGNOP1 were reversed by naltrexone and SB-612111, indicating the involvement of both MOR and NOP receptor agonism. In comparison with morphine, KGNOP1 was more potent and effective in mouse models of inflammatory pain. Unlike morphine, KGNOP1 displayed reduced detrimental liabilities, as no locomotor impairment nor rewarding and withdrawal effects were observed. Docking of KGNOP1 to the MOR and NOP receptors and subsequent 3D interaction pattern analyses provided valuable insights into its binding mode. The mixed MOR/NOP receptor peptide KGNOP1 holds promise in the effort to develop new analgesics for the treatment of various pain states with fewer MOR-mediated side effects, particularly abuse and dependence liabilities.

Abstract 19: Examination of HJC0152, a putative modulator of glucose and energy metabolism, for mammary cancer prevention

Abstract Breast cancer (BC) is the most common cancer in women in the US. Approximately 30-40% of BC cases are estrogen-receptor (ER)-negative (ENBC); the majority of these are triple-negative (TNBC). No drugs have been shown to effectively prevent ENBC including TNBC. TNBC incidence is higher in young African American and Hispanic/Latina women, thus the need for preventive agents for TNBC is critical. Developing agents targeting non-ER-based oncogenic pathways will therefore offer alternative and potentially more effective approaches for preventing ENBC/TNBC. Glucose metabolism is an essential energy-producing process for normal cells and is aberrant and reprogrammed in cancer cells including BC cells. We recently developed HJC0152, a novel small-molecule glucose metabolism modulator as a potential cancer preventive agent. HJC0152 has been shown to inhibit glycolysis by differentially regulating glycolytic enzyme expression and the function of mitochondrial respiratory complexes in both EPBC and TNBC cells, leading to reduced production of energy molecule adenosine-triphosphate (ATP), induced apoptosis, and decreased proliferation and tumor progression. In this study, we determined the preventive anti-cancer efficacies of long-term and short-term (inhibition of premalignant lesions) HJC0152 administration in mouse models of ENBC and TNBC. HJC0152 was given orally 6 days/wk for 2-10 months in well-established ENBC model, MMTV-erbB2; and TNBC model, C3(1)/TAgSV40. HJC0152 at 50 and 75 mg/Kg doses delayed and partially prevented mammary tumor development in ENBC (MMTV-erbB2) mice (p=0.0034 for all groups). A maximum 6-week delay was achieved for median time to tumor formation (TTF). In the TNBC (C3(1)/TAgSV40) model, HJC0152 significantly delayed mammary tumor development (p=0.0114 for all groups) and achieved 3.3-week delay for median TTF. Up to 21% less mice developed mammary tumors in both models. In addition, TNBC mice developed less number of tumors per mouse than in ENBC mice, and the tumor volume doubling time increased from 6.9 to 9.2 days. In the short-term premalignant lesion study, the number of mammary intraepithelial neoplasia (MIN) lesion (representing human DCIS) was significantly decreased (p=0.034) in the HJC0152-treated MMTV-erbB2 mice. In the HJC0152-treated C3(1)/TAgSV40 mice, the number of hyperplasia and MIN lesions were significantly decreased (p=0.0014 and 0.0203, respectively). These results demonstrate that HJC0152 suppresses mammary tumor development in ENBC and TNBC models via reducing premalignant lesions, even in the most aggressive TNBC model, C3(1)/TAgSV40. There were no significant side effects or toxicity signs observed in both long- and short-term prevention experiments. We conclude that HJC0152 has promising cancer preventive efficacy by targeting non-ER-based signaling pathways such as STAT3 signaling and glucose metabolism. This study was supported by a NIH/NCI PREVENT Program fund. *Current Affiliation: LSUHSC. Citation Format: Hyejin Kim, Xi Liu, Yefei Wen, Jia Zhou, Romaine Fernando, Shizuko Sei, Powel H. Brown, Qiang Shen. Examination of HJC0152, a putative modulator of glucose and energy metabolism, for mammary cancer prevention [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 19.

Novel hybrid compounds, opioid agonist+melanocortin 4 receptor antagonist, as efficient analgesics in mouse chronic constriction injury model of neuropathic pain

When the nerve tissue is injured, endogenous agonist of melanocortin type 4 (MC4) receptor, α-MSH, exerts tonic pronociceptive action in the central nervous system, contributing to sustaining the neuropathic pain state and counteracting the analgesic effects of exogenous opioids. With the intent of enhancing opioid analgesia in neuropathy by blocking the MC4 activation, so-called parent compounds (opioid agonist, MC4 antagonist) were joined together using various linkers to create novel bifunctional hybrid compounds. Analgesic action of four hybrids was tested after intrathecal (i.t.) administration in mouse models of acute and neuropathic pain (chronic constriction injury model, CCI). Under nerve injury conditions, one of the hybrids, UW3, induced analgesia in 1500 times lower i.t. dose than the opioid parent (ED50: 0.0002 nmol for the hybrid, 0.3 nmol for the opioid parent) and in an over 16000 times lower dose than the MC4 parent (ED50: 3.33 nmol) as measured by the von Frey test. Two selected hybrids were tested for analgesic properties in CCI mice after intravenous (i.v.) and intraperitoneal (i.p.) administration. Opioid receptor antagonists and MC4 receptor agonists diminished the analgesic action of these two hybrids studied, though the extent of this effect differed between the hybrids; this suggests that linker is of key importance here. Further results indicate a significant advantage of hybrid compounds over the physical mixture of individual pharmacophores in their analgesic effect. All this evidence justifies the idea of synthesizing a bifunctional opioid agonist-linker-MC4 antagonist compound, as such structure may bring important benefits in neuropathic pain treatment.

Exacerbation of disease by intranasal liquid administration following influenza virus infection in mice.

Although numerous studies have clarified the synergistic pathogenesis in mouse models of influenza A virus (IAV)-associated dual infections, fewer studies have investigated the influence of intranasal liquid administration on the disease. This study explored the effects of intranasal PBS administration in mouse models of mimic IAV dual infection and the infectious dose of IAV that caused equivalent pathogenesis in different dual infection models. Weights, survival rates, virus loads, lung indexes and lung pathology were compared. We demonstrated that intranasal PBS administration following H1N1 or H3N2 infection increased weight loss, mortality, virus replication and lung damage. No difference was observed if the order was reversed or PBS was given simultaneously with IAV. To induce equivalent virulence, a 20-fold difference in the infectious dose was needed when the H3N2-PBS superinfection and H3N2-PBS coinfection or PBS-H3N2 superinfection groups were compared. Our study demonstrated that the unfavourable effect of intranasal liquid administration should not be neglected and that both the strain and infectious dose of IAV should be considered to avoid an illusion of synergistic pathogenicity when establishing IAV-associated dual infection model. A 20-fold lower dose than that of coinfection may be a better choice for secondary infection following IAV.

Collaborative membrane activity and receptor-dependent tumor cell targeting for precise nanoparticle delivery in CXCR4+ colorectal cancer

By the appropriate selection of functional peptides and proper accommodation sites, we have generated a set of multifunctional proteins that combine selectivity for CXCR4+ cell binding and relevant endosomal escape capabilities linked to the viral peptide HA2. In particular, the construct T22-GFP-HA2-H6 forms nanoparticles that upon administration in mouse models of human, CXCR4+ colorectal cancer, accumulates in primary tumor at levels significantly higher than the parental T22-GFP-H6 HA2-lacking version. The in vivo application of a CXCR4 antagonist has confirmed the prevalence of the CXCR4+ tumor tissue selectivity over unspecific cell penetration, upon systemic administration of the material. Such specificity is combined with improved endosomal escape, what overall results in a precise and highly efficient tumor biodistribution. These data strongly support the functional recruitment as a convenient approach to generate protein materials for clinical applications. More precisely, they also support the unexpected concept that enhancing the unspecific membrane activity of a protein material does not necessarily compromise, but it can even improve, the selective cell targeting offered by an accompanying functional module. Statement of SignificanceWe have shown here that the combination of cell-penetrating and tumor cell-targeting peptides dramatically enhances precise tumor accumulation of protein-only nanoparticles intended for selective drug delivery, in mouse models of human colorectal cancer. This fact is a step forward for the rational design of multifunctional protein nanomaterials for improved cancer therapies.

Non-invasive early detection of acute transplant rejection via nanosensors of granzyme B activity.

The early detection of the onset of transplant rejection is critical for the long-term survival of patients. The diagnostic gold-standard for detecting transplant rejection involves a core biopsy, which is invasive, has limited predictive power, and carries a morbidity risk. Here, we show that nanoparticles conjugated with a peptide substrate specific for the serine protease granzyme B, which is produced by recipient T cells during the onset of acute cellular rejection, can serve as a non-invasive biomarker of early rejection. Upon systemic administration in mouse models of skin-graft rejection, these nanosensors preferentially accumulate in allograft tissue, where they are cleaved by granzyme B, releasing a fluorescent reporter that filters into the recipient’s urine. Urinalysis then discriminates the onset of rejection with high sensitivity and specificity before features of rejection are apparent in grafted tissues. Moreover, in mice treated with subtherapeutic levels of immunosuppressive drugs, the reporter signals in urine can be detected before graft failure. This method may enable routine monitoring of allograft status without the need for biopsies.

MicroRNAs in alcoholic liver disease: Recent advances and future applications.

Alcoholic liver disease (ALD) is characterized by hepatocyte damage, inflammatory cell activation, and increased intestinal permeability leading to the clinical manifestations of alcoholic hepatitis. Selected members of the family of microRNAs (miRNAs) are affected by alcohol, resulting in an abnormal miRNA profile in the liver and circulation in ALD. Increasing evidence suggests that miRNAs that regulate inflammation, lipid metabolism and promote cancer are affected by excessive alcohol administration in mouse models of ALD. This communication highlights recent findings in miRNA expression and functions as they relate to the pathogenesis of ALD. The cell-specific distribution of miRNAs, as well as the significance of circulating extracellular miRNAs, is discussed as potential biomarkers. Finally, the prospects of miRNA-based therapies are evaluated in ALD.

Therapeutic time window of anti-high mobility group box-1 antibody administration in mouse model of spinal cord injury

Spinal cord injury (SCI) is a devastating neurologic disorder that often leads to permanent disability, and there is no effective treatment for it. High mobility group box-1 (HMGB1) is a damage-associated molecular protein that triggers sterile inflammation upon injuries. We have previously shown that two administrations of neutralizing monoclonal antibody (mAb) against HMGB1 (immediately after (0 h) and 6 h after) SCI dramatically improves functional recovery after SCI in mice. However, when considering clinical application, 0 h after SCI is not practical. Therefore, in this study, we examined the therapeutic time window of the mAb administration. Injection at 3 h after SCI significantly improved the functional recovery comparably to injection immediately after SCI, while injection at 6 h was less effective, and injection at 9 or 12 h had no therapeutic effect. We also found beneficial effects of injection at 3 h after injury on blood-spinal cord barrier maintenance, inflammatory-related gene expression and preservation of the damaged spinal cord tissue. Taken together, our results suggest that a single administration of anti-HMGB1 mAb within a proper time window could be a novel and potential therapeutic strategy for SCI.

Characterization of Chicken IgY Specific to Clostridium difficile R20291 Spores and the Effect of Oral Administration in Mouse Models of Initiation and Recurrent Disease.

Clostridium difficile infection (CDI) are the leading cause of world-wide nosocomial acquired diarrhea. The current main clinical challenge in CDI is the elevated rate of infection recurrence that may reach up to 30% of the patients, which has been associated to the formation of dormant spores during the infection. We sought to characterize the effects of oral administration of specific anti-spore IgY in mouse models of CDI and recurrent CDI. The specificity of anti-spore IgY was evaluated in vitro. In both, initiation mouse model and recurrence mouse model, we evaluated the prophylactic and therapeutic effect of anti-spore IgY, respectively. Our results demonstrate that anti-spore IgY exhibited high specificity and titers against C. difficile spores and reduced spore adherence to intestinal cells in vitro. Administration of anti-spore IgY to C57BL/6 mice prior and during CDI delayed the appearance of the diarrhea by 1.5 day, and spore adherence to the colonic mucosa by 90%. Notably, in the recurrence model, co-administration of anti-spore IgY coupled with vancomycin delayed the appearance of recurrent diarrhea by a median of 2 days. Collectively, these observations suggest that anti-spore IgY antibodies may be used as a novel prophylactic treatment for CDI, or in combination with antibiotics to treat CDI and prevent recurrence of the infection.

Melatonin inhibits snake venom and antivenom induced oxidative stress and augments treatment efficacy

Snakebite is a neglected health hazard. Its patho-physiology has largely been focused on systemic and local toxicities; whereas, venom and antivenom induced oxidative stress has long been ignored. Antivenom therapy although neutralizes venom lethality and saves many lives, remains ineffective against oxidative stress. This prompted us to complement antivenom with an antioxidant molecule melatonin that would protect against oxidative stress and increase the efficacy of the existing snakebite therapy. Here we show that D. russelli and E. carinatus venoms induce strong oxidative stress that persists even after antivenom administration in mice model. Additionally, antivenoms also induce oxidative stress. Polyvalent antivenom induce more oxidative stress than monovalent antivenom. Strikingly, antivenom and melatonin together not only inhibit venom and antivenom induced oxidative stress but also significantly reduce the neutralizing antivenom dose. This study provides a therapeutic potential for enhancing the existing snakebite therapy. The combined treatment of antivenom+melatonin would prevent the upsurge of oxidative stress as well as minimize the antivenom load. Thus the investigation offers immense scope for physicians and toxinologists to reinvestigate, design new strategies and think beyond the conventional mode of antivenom therapy.

Huperzine A Provides Robust and Sustained Protection against Induced Seizures in Scn1a Mutant Mice.

De novo loss-of-function mutations in the voltage-gated sodium channel (VGSC) SCN1A (encoding Nav1.1) are the main cause of Dravet syndrome (DS), a catastrophic early-life encephalopathy associated with prolonged and recurrent early-life febrile seizures (FSs), refractory afebrile epilepsy, cognitive and behavioral deficits, and a 15–20% mortality rate. SCN1A mutations also lead to genetic epilepsy with febrile seizures plus (GEFS+), which is an inherited disorder characterized by early-life FSs and the development of a range of adult epilepsy subtypes. Current antiepileptic drugs often fail to protect against the severe seizures and behavioral and cognitive deficits found in patients with SCN1A mutations. To address the need for more efficacious treatments for SCN1A-derived epilepsies, we evaluated the therapeutic potential of Huperzine A, a naturally occurring reversible acetylcholinesterase inhibitor. In CF1 mice, Hup A (0.56 or 1 mg/kg) was found to confer protection against 6 Hz-, pentylenetetrazole (PTZ)-, and maximal electroshock (MES)-induced seizures. Robust protection against 6 Hz-, MES-, and hyperthermia-induced seizures was also achieved following Hup A administration in mouse models of DS (Scn1a+/−) and GEFS+ (Scn1aRH/+). Furthermore, Hup A-mediated seizure protection was sustained during 3 weeks of daily injections in Scn1aRH/+ mutants. Finally, we determined that muscarinic and GABAA receptors play a role in Hup A-mediated seizure protection. These findings indicate that Hup A might provide a novel therapeutic strategy for increasing seizure resistance in DS and GEFS+, and more broadly, in other forms of refractory epilepsy.

Preclinical voluntary drinking models for alcohol abstinence-induced affective disturbances in mice.

Negative reinforcement is widely thought to play an important role in chronic alcohol-use disorders (AUDs), and high comorbidity between AUDs and affective disorders highlights the importance of investigating this relationship. Prominent models posit that repeated cycles of alcohol (ethanol, EtOH) exposure and withdrawal produce circuit adaptations in the central nervous system that drive a transition from positive- to negative reinforcement-based alcohol seeking. Evidence supporting this theory has accumulated in large part using forced EtOH administration models, such as chronic intragastric gavage and chronic vapor inhalation. However, recent studies utilizing simple voluntary EtOH delivery systems show that forced abstinence from EtOH intake administered by the animal itself can produce evolving and significant affective disturbances, particularly in female C57BL/6J mice. Here, we highlight these recent studies to support the idea that voluntary EtOH administration in mouse models, as well as a protracted abstinence period and less commonly used behavioral tasks, could unveil affective disturbances during abstinence that have remained elusive using high dosage forced EtOH administration paradigms.

Percutaneous Vaccination as an Effective Method of Delivery of MVA and MVA-Vectored Vaccines.

The robustness of immune responses to an antigen could be dictated by the route of vaccine inoculation. Traditional smallpox vaccines, essentially vaccinia virus strains, that were used in the eradication of smallpox were administered by percutaneous inoculation (skin scarification). The modified vaccinia virus Ankara is licensed as a smallpox vaccine in Europe and Canada and currently undergoing clinical development in the United States. MVA is also being investigated as a vector for the delivery of heterologous genes for prophylactic or therapeutic immunization. Since MVA is replication-deficient, MVA and MVA-vectored vaccines are often inoculated through the intramuscular, intradermal or subcutaneous routes. Vaccine inoculation via the intramuscular, intradermal or subcutaneous routes requires the use of injection needles, and an estimated 10 to 20% of the population of the United States has needle phobia. Following an observation in our laboratory that a replication-deficient recombinant vaccinia virus derived from the New York City Board of Health strain elicited protective immune responses in a mouse model upon inoculation by tail scarification, we investigated whether MVA and MVA recombinants can elicit protective responses following percutaneous administration in mouse models. Our data suggest that MVA administered by percutaneous inoculation, elicited vaccinia-specific antibody responses, and protected mice from lethal vaccinia virus challenge, at levels comparable to or better than subcutaneous or intramuscular inoculation. High titers of specific neutralizing antibodies were elicited in mice inoculated with a recombinant MVA expressing the herpes simplex type 2 glycoprotein D after scarification. Similarly, a recombinant MVA expressing the hemagglutinin of attenuated influenza virus rgA/Viet Nam/1203/2004 (H5N1) elicited protective immune responses when administered at low doses by scarification. Taken together, our data suggest that MVA and MVA-vectored vaccines inoculated by scarification can elicit protective immune responses that are comparable to subcutaneous vaccination, and may allow for antigen sparing when vaccine supply is limited.