Treatment Of Animal Models Research Articles

Evaluation of Serum Cytokines Levels and the Role of Cannabidiol Treatment in Animal Model of Asthma.

Asthma represents a public health problem and traditionally is classified as an atopic disease, where the allergen can induce clinical airway inflammation, bronchial hyperresponsiveness, and reversible obstruction of airways. Studies have demonstrated the presence of T-helper 2 lymphocytes in the lung of patients with asthma. These cells are involved in cytokine production that regulates immunoglobulin synthesis. Recognizing that T cell interaction with antigens/allergens is key to the development of inflammatory diseases, the aim of this study is to evaluate the anti-inflammatory potential of cannabidiol (CBD) in this setting. Asthma was induced in 8-week-old Wistar rats by ovalbumin (OVA). In the last 2 days of OVA challenge animals received CBD (5 mg/kg, i.p.) and were killed 24 hours after. The levels of IL-4, IL-5, IL-13, IL-6, IL-10, and TNF-α were determinate in the serum. CBD treatment was able to decrease the serum levels of all analyzed cytokines except for IL-10 levels. CBD seems to be a potential new drug to modulate inflammatory response in asthma.

Inhibition of microglial activation and induction of neurotrophic factors by flavonoids: a potential therapeutic strategy against Parkinson's disease.

Parkinson’s disease(PD)is characterized by the progressive degeneration of dopaminergic(DA)neurons and a decrease in striatal dopamine,which is associated with clinical movement disorders including a tremor at rest,rigidity of the limbs,bradykinesia(slowness and paucity of voluntary movement)and postural instability(a tendency to fall even in the absence of

Immune therapy for treating type 1 diabetes: challenging existing paradigms.

Patients with type 1 diabetes (T1D) rapidly lose β cell function and/or mass, leading to a life-long dependence on insulin therapy. β Cell destruction is mediated by aberrant immune responses; therefore, immune modulation has potential to ameliorate disease. While immune intervention in animal models of diabetes has shown promising results, treatment of patients with T1D with the same agents has not been as successful. In this issue of the JCI, Haller and colleagues present data from a small clinical trial that tested the efficacy of a combination of immunomodulatory agents, anti-thymocyte globulin and pegylated granulocyte CSF, neither of which have shown benefit for T1D as single treatment agents. Many patients that received combination therapy maintained β cell function at baseline levels up to a year after treatment. The results from this study challenge current trial design paradigm that for combined therapy to be successful individual agents should show benefit.

What are the Best Animal Models for Testing Early Intervention in Cerebral Palsy?

Interventions to treat cerebral palsy should be initiated as soon as possible in order to restore the nervous system to the correct developmental trajectory. One drawback to this approach is that interventions have to undergo exceptionally rigorous assessment for both safety and efficacy prior to use in infants. Part of this process should involve research using animals but how good are our animal models? Part of the problem is that cerebral palsy is an umbrella term that covers a number of conditions. There are also many causal pathways to cerebral palsy, such as periventricular white matter injury in premature babies, perinatal infarcts of the middle cerebral artery, or generalized anoxia at the time of birth, indeed multiple causes, including intra-uterine infection or a genetic predisposition to infarction, may need to interact to produce a clinically significant injury. In this review, we consider which animal models best reproduce certain aspects of the condition, and the extent to which the multifactorial nature of cerebral palsy has been modeled. The degree to which the corticospinal system of various animal models human corticospinal system function and development is also explored. Where attempts have already been made to test early intervention in animal models, the outcomes are evaluated in light of the suitability of the model.

Intravenous immunoglobulin-related thromboembolic events - an accusation that proves the opposite

Intravenous immunoglobulin-related thromboembolic events - an accusation that proves the opposite

Abstract 2054: Patient relevant preclinical in vivo models using image-guided small animal irradiation for drug discovery

Abstract BACKGROUND: Radiotherapy is a primary, adjuvant or neoadjuvant treatment for a number of different cancers such as glioblastoma, breast, lung and prostate. Image-guided radiotherapy (IGRT) is widely used to treat cancer patients providing more accurate treatment plans and reduced side effects. However in the preclinical setting the use of IGRT is less common with traditional irradiation studies utilising whole body irradiation with lead shielding attempting to focus the radiation to specific area on the animal or simple single beam techniques. The development of the image-guided small animal radiation research platform (SARRP) allows the treatment of animal models of cancer more accurately and importantly, with planned protocols similar to those utilised in the clinic. In addition the high precision beam geometry allows the platform to be used in vitro in multi-well assays providing a more high-throughput system for screening. METHODS: We have established multiple cancer models which incorporate bioluminescence to track primary orthotopic and metastatic lesions in real-time using the Spectrum CT imaging system. Tumor growth was monitored longitudinally through quantification of the bioluminescent signal. Bioluminescence from established tumor was correlated to CT and co-registered with the integrated CT on the SARRP platform to allow estimation of tumor dimensions and position in order to deliver a more accurate dose of irradiation specifically to tumors whilst sparing the surrounding normal tissue. In addition we have established Caucasian non-small cell lung cancer (NSCLC) patient-derived xenograft (PDX) models which are admixed with human stroma and evaluated SARRP in these. Tumor specific protocols and dose calculation for irradiation were designed to deliver appropriate irradiation dose to immuno-deficient mice bearing xenografted tumor either alone or in combination with targeted agent or chemotherapeutic. RESULTS: Mice treated with SARRP tolerated irradiation doses in a range of different models either alone or in combination. Validation of different protocols will be reported as well as intrinsic resistant profiles for different models and outcome of any combination treatments to re-sensitize resistant cancer to radiotherapy. CONCLUSIONS: The SARRP platform allows the use of irradiation alone or in combination with anti-cancer agents in small animals with reduced side effects and improved clinical outcome allowing these novel preclinical models to be used effectively for drug discovery programmes to ultimately improve efficacy and treatment options for cancer patients using radiotherapy. Citation Format: Rajendra Kumari, Andrew McKenzie, Nektaria Papadopoulou, Yinfei Yin, Martin Page, Henry Li, Ian Wilson. Patient relevant preclinical in vivo models using image-guided small animal irradiation for drug discovery. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2054. doi:10.1158/1538-7445.AM2014-2054

The inflammophilic character of the periodontitis‐associated microbiota

In periodontitis, dysbiotic microbial communities exhibit synergistic interactions for enhanced protection from host defenses, nutrient acquisition, and persistence in an inflammatory environment. This review discusses evidence that periodontitis-associated communities are 'inflammo-philic' (=loving or attracted to inflammation) in that they have evolved to not only endure inflammation but also to take advantage of it. In this regard, inflammation can drive the selection and enrichment of these pathogenic communities by providing a source of nutrients in the form of tissue breakdown products (e.g. degraded collagen peptides and heme-containing compounds). In contrast, those species that cannot benefit from the altered ecological conditions of the inflammatory environment, or for which host inflammation is detrimental, are likely to be outcompeted. Consistent with the concept that inflammation fosters the growth of dysbiotic microbial communities, the bacterial biomass of human periodontitis-associated biofilms was shown to increase with increasing periodontal inflammation. Conversely, anti-inflammatory treatments in animal models of periodontitis were shown to diminish the periodontal bacterial load, in addition to protecting from bone loss. The selective flourishing of inflammophilic bacteria can perpetuate inflammatory tissue destruction by setting off a 'vicious cycle' for disease progression, in which dysbiosis and inflammation reinforce each other. Therefore, the control of inflammation appears to be central to the treatment of periodontitis, as it is likely to control both dysbiosis and disease progression.

Growth Factor Delivered by a Bioabsorbable Polymer as Treatment for Chronic Tympanic Membrane Perforations

Objectives: (1) Test the efficacy of a novel topical growth factor (GF) treatment, delivered by a bioabsorbable polymer, in animal models of chronic tympanic membrane (TM) perforation, Eustachian tube (ET) obstruction, and chronic suppurative otitis media (CSOM). (2) Describe the preclinical work forming the basis for a proposed clinical trial of topical GF treatment. Methods: Bilateral chronic TM perforations were created in our novel mouse model (n = 50) and stable at 3 months, using an inhibitor of epidermal growth factor receptor. One ear received topical GF polymer treatment and the other received polymer only. Another mice cohort (n = 42) had chronic perforations created and also surgical obstruction of the ET. A further mice cohort (n = 35) had CSOM created through the above procedure and inoculation of pseudomonas aeruginosa. These perforations and treatments were evaluated microscopically, histologically, and using cytokeratin immunohistochemistry. Toxicity and safety of our polymer and GF were evaluated using auditory brain stem responses (ABR) and otoacoustic emissions (OAE) at 8 weeks following treatment. Results: In the chronic TM perforation cohort, 92% (22 of 24) healed compared with 38% (10 of 26) of controls (polymer only) at 4 weeks ( P < .01). In the chronic perforation cohort with ET obstruction, 94% (18 of 19) healed compared with 9% (2 of 23) of controls (polymer only) at 6 weeks ( P < .01). The ABR and OAE of our cohorts returned to control levels at 8 weeks. Conclusions: We demonstrate the efficacy, safety, and nontoxicity of a novel GF treatment in animal models.

A systematic review of preclinical studies on the therapeutic potential of mesenchymal stromal cell-derived microvesicles.

The therapeutic potential of mesenchymal stromal cells (MSCs) may be largely mediated by paracrine factors contained in microvesicles (MV) released from intracellular endosomes. A systematic review of controlled interventional animal studies was performed to identify models of organ injury where clinical translation of MSC-derived microvesicle therapy appears most promising as regenerative therapy. A total of 190 published articles were identified in our systematic search of electronic databases (MEDLINE, EMBASE, PUBMED). After screening for eligibility, a total of 17 controlled studies testing MSC-derived MVs as therapeutic interventions in animal models of disease underwent comprehensive review, quality assessment, and data extraction. Thirteen studies addressed the regenerative potential following organ injury. Six studies were included on acute kidney injury, 4 on myocardial infarction and reperfusion injury, 1 on hind limb ischemia, 1 on liver injury, and 1 on hypoxic lung injury. Four studies addressed immunological effects of MSC-derived MVs on inhibiting tumor growth. Twelve studies (71%) provided explicit information regarding the number of animals allocated to treatment or control groups. Five studies (29%) randomly assigned animals to treatment or control groups and only 1 study (6%) reported on blinding. Therapeutic intervention involved isolation of exosomes (40-100 nm) in eight studies, while nine studies tested unfractionated microvesicles (<1,000 nm). In studies of tissue regeneration, all 13 reported that treatment with MSC-derived MVs improved at least one major/clinical parameter associated with organ dysfunction. Three of 4 studies evaluating the inhibition of tumor growth reported benefit. In preclinical studies, the use of MSC-derived MVs is strongly associated with improved organ function following injury and may be useful for inhibiting tumor growth. Improved preclinical study quality in terms of treatment allocation reporting, randomization and blinding will accelerate needed progress towards clinical trials that should assess feasibility and safety of this therapeutic approach in humans.

Treatment of acute lung injury by targeting MG53-mediated cell membrane repair.

Injury to lung epithelial cells has a role in multiple lung diseases. We previously identified mitsugumin 53 (MG53) as a component of the cell membrane repair machinery in striated muscle cells. Here we show that MG53 also has a physiological role in the lung and may be used as a treatment in animal models of acute lung injury. Mice lacking MG53 show increased susceptibility to ischemia-reperfusion and over-ventilation induced injury to the lung when compared with wild type mice. Extracellular application of recombinant human MG53 (rhMG53) protein protects cultured lung epithelial cells against anoxia/reoxygenation-induced injuries. Intravenous delivery or inhalation of rhMG53 reduces symptoms in rodent models of acute lung injury and emphysema. Repetitive administration of rhMG53 improves pulmonary structure associated with chronic lung injury in mice. Our data indicate a physiological function for MG53 in the lung and suggest that targeting membrane repair may be an effective means for treatment or prevention of lung diseases.

Caveolin-1 as a biomarker to predict therapeutic effect of low-frequency ultrasound combined with SonoVue on prostate cancer in nude mice model.

Caveolin-1 is a major structural component of cell membrane invaginations. Over-expression of caveolin-1 is closely related to the tumorigenesis and progression of prostate cancer. Recently, contrast microbubbles in combination with ultrasound are being investigated for their therapeutic applications in tumor cells. However, the response of caveolin-1 after low-frequency ultrasound and SonoVue treatment in animal model is unclear. The goal of this study was to evaluate the effect of 80 kHz ultrasound and/or SonoVue on caveolin-1 expression and secretion in DU145 prostate tumors in nude mice. Six-week-old BALB/c male nude mice were subcutaneously injected with DU145 cells in the right flank to establish a prostate cancer model, which were randomly divided into four groups (n=8 each): control group (sham-ultrasound exposure), SonoVue group, 80 kHz ultrasound group, 80 kHz ultrasound combined with SonoVue group. Tumor volumes and wet weights were measured, and the tumor volume curve was obtained as well. The mice were euthanized 21 days after treatment. Specimens of the tumor tissues were assessed the expression of caveolin-1 by immunohistochemistry and Western blot. The serum concentrations of caveolin-1 were detected by ELISA. Treatment with ultrasound alone produced tumor volumes and weights reduction compared with control and SonoVue group. Combined ultrasound and SonoVue treatment produced greater tumor regression than either treatment alone (p < 0.05). Serum caveolin-1 concentrations were lower in the combination of ultrasound and SonoVue group than they were in control group (p =0.005), and had some certain correlation with tumor growth (wet weight) (r =0.507), although the difference was not statistically significant (p=0.199). Ultrasound alone treatment only slightly reduced the caveolin-1 concentrations in comparison with the control, and the difference was not statistically significant (p=0.125). The ultrasound-treated mice showed significant reduction in expression levels of caveolin-1 protein, compared with the control (p < 0.05). Levels of caveolin-1 were further reduced when combined with ultrasound and SonoVue as compared to the control (p < 0.01). Our results suggest that 80 kHz ultrasound have antitumor effect and the effect could be further strengthened by the combination of SonoVue. Down-regulating the expression of caveolin-1 is likely a potential biomarker of response to ultrasound and SonoVue treatment in prostate cancer mouse model.

Induction of GDNF and BDNF by hRheb(S16H) transduction of SNpc neurons: neuroprotective mechanisms of hRheb(S16H) in a model of Parkinson's disease.

The transduction of dopaminergic (DA) neurons with human ras homolog enriched in brain, which has a S16H mutation [hRheb(S16H)] protects the nigrostriatal DA projection in the 6-hydroxydopamine (6-OHDA)-treated animal model of Parkinson's disease (PD). However, it is still unclear whether the expression of active hRheb induces the production of neurotrophic factors such as glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF), which are involved in neuroprotection, in mature neurons. Here, we show that transduction of nigral DA neurons with hRheb(S16H) significantly increases the levels of phospho-cyclic adenosine monophosphate (cAMP) response element-binding protein (p-CREB), GDNF, and BDNF in neurons, which are attenuated by rapamycin, a specific inhibitor of mammalian target of rapamycin complex 1 (mTORC1). Moreover, treatment with specific neutralizing antibodies for GDNF and BDNF reduced the protective effects of hRheb(S16H) against 1-methyl-4-phenylpyridinium (MPP(+))-induced neurotoxicity. These results show that activation of hRheb/mTORC1 signaling pathway could impart to DA neurons the important ability to continuously produce GDNF and BDNF as therapeutic agents against PD.

Chronic repetitive transcranial magnetic stimulation enhances GABAergic and cholinergic metabolism in chronic unpredictable mild stress rat model: 1H-NMR spectroscopy study at 11.7 T

Gamma-animobutyric acid (GABA) systems are emerging as targets for development of medications for mood disorders. Deficits in GABA-containing neurons are consistently reported in psychiatric disease, particularly in the prefrontal cortex and hippocampus. Repetitive transcranial magnetic stimulation (rTMS) that use magnetic field to stimulate focal cortical regions with electrical current have a potential therapeutic effects with non-invasive and painless method. In this study, we used chronic unpredictable mild stress (CUMS) rat model of depression to investigate the behavioral and neurochemical alterations. Furthermore, chronic rTMS treatment effect on neurochemical profile in prefrontal cortex and hippocampus of rats were assessed. The CUMS induced significant reductions in absolute sucrose intake and sucrose preference. In addition, high-resolution 1H-NMR spectra from brain extracts revealed significantly reduced prefrontal and hippocampal GABA levels in CUMS rats compared to control. The behavioral and neurochemical changes were reversed by chronic rTMS treatment. Furthermore, chronic rTMS treatments results in differential effects on different brain regions. Our results suggest specific and regionally different metabolic response to chronic rTMS treatment in animal model of depression.

Modulation of early stress-induced neurobiological changes: a review of behavioural and pharmacological interventions in animal models.

Childhood adversity alters the predisposition to psychiatric disorders later in life. Those with psychiatric conditions and a history of early adversity exhibit a higher incidence of treatment resistance compared with individuals with no such history. Modulation of the influence early stress exerts over neurobiology may help to prevent the development of psychiatric disorders in some cases, while attenuating the extent of treatment resistance in those with established psychiatric disorders. This review aims to critically evaluate the ability of behavioural, environmental and pharmacologic interventions to modulate neurobiological changes induced by early stress in animal models. Databases were systematically searched to locate literature relevant to this review. Early adversity was defined as stress that resulted from manipulation of the mother–infant relationship. Analysis was restricted to animal models to enable characterisation of how a given intervention altered specific neurobiological changes induced by early stress. A wide variety of changes in neurobiology due to early stress are amenable to intervention. Behavioural interventions in childhood, exercise in adolescence and administration of epigenetic-modifying drugs throughout life appear to best modulate cellar and behavioural alterations induced by childhood adversity. Other pharmacotherapies, such as endocannabinoid system modulators, anti-inflammatories and antidepressants can also influence these neurobiological and behavioural changes that result from early stress, although findings are less consistent at present and require further investigation. Further work is required to examine the influence that behavioural interventions, exercise and epigenetic-modifying drugs exert over alterations that occur following childhood stress in human studies, before possible translational into clinical practice is possible.

Novel ethological endophenotypes in a transgenic mouse model of Huntington's disease

Huntington's disease (HD) is an autosomal dominant, neurodegenerative disorder with a characteristic triad of cognitive, affective and motor symptoms. Transgenic HD mice show excellent construct and face validity for many of these symptoms, however the decline in some facets of every day activity in humans is difficult to model. One approach is the assessment of species-relevant behaviors. Here we described three ethologically appropriate tests in the mouse—olfactory sensitivity, nest-building and sexually-motivated vocalizations. In R6/1 HD mice, olfactory and nest-building tests were sensitive to early dysfunctions induced by the HD mutation. Male vocalization testing revealed a late-stage sexual disinterest in R6/1 HD mice compared to WT littermates. We show that essential, species-relevant functions are disrupted by the HD mutation. The development of integrative behavioral assays which more closely model ‘activities of daily living’ (ADL) will facilitate the testing of novel therapeutic interventions in animal models as well as their clinical translation.

Epinephrine for Cardiac Arrest

Epinephrine for Cardiac Arrest: Are We Doing More Harm Than Good? Vijay Krishnamoorthy;Monica Vavilala;Michael Fettiplace;Guy Weinberg; Anesthesiology

Clozapine-induced paralytic ileus: a case report.

Ileus is the disruption of the normal propulsive ability of the gastrointestinal tract and it represents 20% of acute abdominal pain cases. Renal failure, hypovolemic shock, organ hypoperfusion, bowel perforation, peritonitis and sepsis, are serious and potentially fatal consequences of ileus. All of the psychotropic drugs with anticholinergic side effects can result in a change in bowel movements which may result in paralytic ileus. Paralytic ileus cases have been reported related to the anticholinergic side effects in the use of antidepressants such as amitriptyline, clomipramine and imipramine; and first-generation antipsychotics such as chlorpromazine, thioridazine and flupenthixol. Second-generation antipsychotics can cause a very rare paralytic ileus [Luzny et al. 2010; Rondla and Crane 2007; Giordano et al. 1975; Gaszner et al. 2004; Hayes et al. 1987; Fayad and Brujinzeel, 2012; Ramamourthy et al. 2013]. In the literature, advanced age, female gender, first-generation antipsychotics, tricyclic antidepressants, anticholinergics and opioids are reported as risk factors for ileus in patients with schizophrenia [Nielsen and Meyer, 2012]. The main reason for ileus being associated with clozapine is the muscarinic anticholinergic activity of clozapine. It has been also suggested that clozapine may induce an infection or ileus may develop depending on the dose of the toxicity [Rondla and Crane 2007; Nielsen and Meyer, 2012; Darling and Huthwaite, 2011; Solanki et al. 2007]. Indeed, after the treatment of animal models with antipsychotics, bowel structure inflammation, edema and bleeding have been reported in the intestinal structure [Luzny et al. 2010; Rondla and Crane, 2007]. Another present mechanism is the immobility caused by the H1 antagonism. 5HT receptors which are effective in gastrointestinal motility may also be effective in the etiology [Nielsen and Meyer, 2012]. A schizophrenic patient who developed paralytic ileus after the use of clozapine has been presented as a case study below.

Silibinin Attenuates MPP+-Induced Neurotoxicity in the Substantia NigraIn Vivo

Parkinson's disease (PD) is characterized by degeneration of the nigrostriatal dopaminergic (DA) pathway. The cause of neuronal death in PD is largely unknown, but it is becoming clear that inflammation plays a significant role in the pathophysiology of PD. Silibinin is a major flavonoid in milk thistle which has an anti-inflammatory activity. We investigated whether silibinin could have neuroprotective effects on DA neurons in the 1-methyl-4-phenylpyridinium ion (MPP(+))-treated animal model of PD in vivo. To address this question, animals received intraperitoneal (i.p.) injections 10, 50, or 100 mg/kg of silibinin, starting 1 day before MPP(+) injection and continued daily until 6 days post-lesion for tyrosine hydroxylase (TH) staining, or until 1 hour prior to the MPP(+) injection to examine the expression levels of inflammatory proteins. Finally, their brains were harvested at the indicated time points for the analyses. Silibinin treatment with 10 mg/kg had no significantly neuroprotective effects in the substantia nigra (SN). However, 50 and 100 mg/kg of silibinin ameliorated the MPP(+)-induced neurotoxicity in the SN in a dose-dependent manner, and the increased levels of inflammatory molecules such as tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and inducible nitric oxide synthase (iNOS) by MPP(+) treatment were attenuated by treatment with 100 mg/kg of silibinin. These results indicate that silibinin could be a useful and beneficial natural product offering promise for the prevention of DA neuronal degeneration involved in PD.

Recent insights into the identity of mesenchymal stem cells

The ability of mesenchymal stem cells (MSCs) to differentiate in vitro into chondrocytes, osteocytes and myocytes holds great promise for tissue engineering. Skeletal defects are emerging as key targets for treatment using MSCs due to the high responsiveness of bone to interventions in animal models. Interest in MSCs has further expanded in recognition of their ability to release growth factors and to adjust immune responses. Despite their increasing application in clinical trials, the origin and role of MSCs in the development, repair and regeneration of organs have remained unclear. Until recently, MSCs could only be isolated in a process that requires culture in a laboratory; these cells were being used for tissue engineering without understanding their native location and function. MSCs isolated in this indirect way have been used in clinical trials and remain the reference standard cellular substrate for musculoskeletal engineering. The therapeutic use of autologous MSCs is currently limited by the need for ex vivo expansion and by heterogeneity within MSC preparations. The recent discovery that the walls of blood vessels harbour native precursors of MSCs has led to their prospective identification and isolation. MSCs may therefore now be purified from dispensable tissues such as lipo-aspirate and returned for clinical use in sufficient quantity, negating the requirement for ex vivo expansion and a second surgical procedure. In this annotation we provide an update on the recent developments in the understanding of the identity of MSCs within tissues and outline how this may affect their use in orthopaedic surgery in the future.

Systematic review and meta-analysis of interventions tested in animal models of lacunar stroke.

A total of 25% of strokes are lacunar, and these are pathophysiologically different from large artery strokes. Despite emerging evidence of a substantial impact on physical disability and dementia, little attention has been paid to the development of specific treatments. The optimal use of the animal models of lacunar stroke used to test candidate interventions is not known. We conducted a systematic review and meta-analysis of studies testing candidate interventions in animal models of lacunar stroke. We used random-effects meta-analysis to assess the impact of study characteristics and trim and fill to seek evidence of publication bias. The efficacy of 43 distinct interventions was described in 57 publications. The median number of quality checklist items scored was 3 of 8 (interquartile range, 2-4). Many models reflected mechanisms of limited relevance to lacunar stroke. Meta-analysis of results from 27 studies showed that on average, infarct size and neurobehavioral outcome were improved by 34.2% (24.1-44.2) and 0.82 standardized mean difference (0.51-1.14), respectively. Four interventions improved both infarct size and neurobehavioral outcome but there were insufficient data for this finding to be considered robust. For infarct size, efficacy was lower in studies reporting blinding and higher in studies reporting randomization. For neurobehavior, efficacy was lower in randomized studies. For infarct size there was evidence of publication bias. No intervention has yet been tested in sufficient range and depth to support translation to clinical trial. There is limited reporting of measures to reduce the risk of bias and evidence for a substantial publications bias.