Exploring parental cystic fibrosis disclosure to well children.

Cystic fibrosis (CF), a genetic disease and chronic illness, affects multiple organ systems and requires exceptional medical care and treatment. Few studies have assessed the diagnosis disclosure process to well children when their sibling(s) have CF, and none have evaluated the association between parental knowledge of CF and the disclosure of CF. The objectives of this study were to assess parental understanding of CF, demonstrate the most commonly shared topics and their frequencies of discussion with well children, and identify associations between parental understanding of CF and aspects of the disclosure process to well children. Parents were recruited from CF support organizations and asked to complete an online, anonymous survey. Individuals were eligible to participate in the study if they had at least one living child with CF and at least one living child without CF. Completed surveys from 48 individuals revealed that most parents began discussing a sibling's diagnosis of CF with the first-born well child at 5.4 years old. Topics related to CF were discussed openly and as needed with their well children (n = 44). The most frequently discussed topic, and the topic ranked most important (1.93 of 5, SD: 1.17) by 40 participants (90.9%), was medical concerns and treatment for CF. Fewer parents (n = 18, 40.9%) reported discussing the financial impact of CF, and many ranked this as least important to share (4.64 of 5, SD: 0.75). The CF knowledge assessment revealed that participants were well-informed about CF, with a mean total score of 8.9/10 (SD: 0.91). There were no associations between CF knowledge assessment scores, education level, income, and the topics discussed with well children. These results can be utilized by genetic counselors and other healthcare specialists in discussion with parents about the disclosure process of a diagnosis of CF to well children.

Comparing substance use and mental health among sexual and gender minority and heterosexual cisgender youth experiencing homelessness.

Youth homelessness has been demonstrated to disproportionately affect sexual and gender minority (SGM) youth compared to heterosexual cisgender peers. In this context, we aimed to compare health risks between service-seeking SGM and heterosexual cisgender youth experiencing homelessness, including harmful risks stemming from substance use and severity of symptoms of mental health disorders. We recruited 100 racially diverse, unstably housed participants aged 18-24 who access services at an urban non-profit organization in San Francisco, CA. Data analysis included 56 SGM participants who identified as gay, lesbian, bisexual, pansexual, unsure, transgender, and nongender, and 44 heterosexual cisgender participants. In contrast to previous studies reporting significantly higher frequency of substance use and more severe symptoms of depression, generalized anxiety, and post-traumatic stress disorder among SGM youth compared to heterosexual cisgender peers, many of these health disparities were not observed in our diverse study population of service-seeking youth. Furthermore, with the exception of methamphetamine, SGM participants did not exhibit greater harmful risks resulting from substance use, such as health, social, financial, and legal complications. We discuss the reduced burden of health disparities between SGM and heterosexual cisgender youth in our service-seeking study population within the context of gender- and sexuality-affirming programming offered at the partnering community organization. We conclude that longitudinal data on these tailored community-level interventions are needed to further explore the reduced burden of health disparities observed among service-seeking SGM youth experiencing homelessness in San Francisco in order to continue supporting pathways out of homelessness for youth of all sexual and gender identities nationwide.

Challenges and opportunities for integrating genetic testing into a diagnostic workflow: heritable long QT syndrome as a model.

BACKGROUND: An increasing number of diagnostic evaluations incorporate genetic testing to facilitate accurate and timely diagnoses. The increasing number and complexity of genetic tests continue to pose challenges in deciding when to test, selecting the correct test(s), and using results to inform medical diagnoses, especially for medical professionals lacking genetic expertise. Careful consideration of a diagnostic workflow can be helpful in understanding the appropriate uses of genetic testing within a broader diagnostic workup. CONTENT: The diagnosis of long QT syndrome (LQTS), a life-threatening cardiac arrhythmia, provides an example for this approach. Electrocardiography is the preferred means for diagnosing LQTS but can be uninformative for some patients due to the variable presentation of the condition. Family history and genetic testing can augment physiological testing to inform a diagnosis and subsequent therapy. Clinical and laboratory professionals informed by peer- reviewed literature and professional recommendations constructed a generalized LQTS diagnostic workflow. This workflow served to explore decisions regarding the use of genetic testing for diagnosing LQTS. SUMMARY AND OUTLOOK: Understanding the complexities and approaches to integrating genetic testing into a broader diagnostic evaluation is anticipated to support appropriate test utilization, optimize diagnostic evaluation, and facilitate a multidisciplinary approach essential for achieving accurate and timely diagnoses.

HNRNPH1-related syndromic intellectual disability: Seven additional cases suggestive of a distinct syndromic neurodevelopmental syndrome.

Pathogenic variants in HNRNPH1 were first reported in 2018. The reported individual, a 13 year old boy with a c.616C>T (p.R206W) variant in the HNRNPH1 gene, was noted to have overlapping symptoms with those observed in HNRNPH2-related X-linked intellectual disability, Bain type (MRXSB), specifically intellectual disability and dysmorphic features. While HNRNPH1 variants were initially proposed to represent an autosomal cause of MRXSB, we report an additional seven cases which identify phenotypic differences from MRXSB. Patients with HNRNPH1 pathogenic variants diagnosed via WES were identified using clinical networks and GeneMatcher. Features unique to individuals with HNRNPH1 variants include distinctive dysmorphic facial features; an increased incidence of congenital anomalies including cranial and brain abnormalities, genitourinary malformations, and palate abnormalities; increased incidence of ophthalmologic abnormalities; and a decreased incidence of epilepsy and cardiac defects compared to those with MRXSB. This suggests that pathogenic variants in HNRNPH1 result in a related, but distinct syndromic cause of intellectual disability from MRXSB, which we refer to as HNRNPH1-related syndromic intellectual disability.

Trauma, substance use, and mental health symptoms in transitional age youth experiencing homelessness.

OBJECTIVE: This descriptive study examined the prevalence and correlates of trauma, substance use, and mental health symptoms in homeless transitional age youth (TAY) in San Francisco. DESIGN & SAMPLE: One hundred homeless TAY were recruited from a community-based organization to complete a survey on trauma, mental health symptoms, and substance use. MEASUREMENTS: We used these measures: National Institute on Drug Abuse (NIDA)-Modified Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) for frequency and risk level of substance use; the 10-item Adverse Childhood Experiences (ACEs) for prevalence of trauma; the Post-traumatic Stress Disorder Checklist for DSM-5 for post-traumatic stress disorder (PTSD) symptoms; Center for Epidemiologic Studies Depression Scale for depression symptoms; and Generalized Anxiety Disorder 7-item for anxiety symptoms. RESULTS: Almost all (n = 98) participants experienced at least one ACE during childhood, and 77% experienced four or more. Most participants (80%) reached the diagnostic threshold for PTSD, 74% for depression, and 51% for moderate anxiety. Symptoms of PTSD, anxiety, and depression were all significantly correlated with use of opioids and stimulants. CONCLUSION: Trauma, and co-occurring substance use and mental health problems are prevalent among homeless TAY. Individual- and community-level interventions are needed to address and improve the health of this population.

First-in-Class Phosphorylated-p68 Inhibitor RX-5902 Inhibits ß-Catenin Signaling and Demonstrates Antitumor Activity in Triple-Negative Breast Cancer.

RX-5902 is a first-in-class anticancer agent targeting phosphorylated-p68 and attenuating nuclear shuttling of ß-catenin. The purpose of this study was to evaluate the efficacy of RX-5902 in preclinical models of triple-negative breast cancer (TNBC) and to explore effects on ß-catenin expression. A panel of 18 TNBC cell lines was exposed to RX-5902, and changes in proliferation, apoptosis, cellular ploidy, and effector protein expression were assessed. Gene expression profiling was used in sensitive and resistant cell lines with pathway analysis to explore pathways associated with sensitivity to RX-5902. The activity of RX-5902 was confirmed in vivo in cell line and patient-derived tumor xenograft (PDX) models. RX-5902 demonstrated potent antiproliferative activity in vitro against TNBC cell lines with an average IC50 of 56 nmol/L in sensitive cell lines. RX-5902 treatment resulted in the induction of apoptosis, G2-M cell-cycle arrest, and aneuploidy in a subset of cell lines. RX-5902 was active in vivo against TNBC PDX models, and treatment resulted in a decrease in nuclear ß-catenin. RX-5902 exhibited dose-proportional pharmacokinetics and plasma and tumor tissue in nude mice. Pathway analysis demonstrated an increase in the epithelial-to-mesenchymal transformation (EMT), TGFß, and Wnt/ß-catenin pathways associated with sensitivity to RX-5902. RX-5902 is active against in vitro and in vivo preclinical models of TNBC. Target engagement was confirmed with decreases in nuclear ß-catenin and MCL-1 observed, confirming the proposed mechanism of action. This study supports the continued investigation of RX-5902 in TNBC and combinations with immunotherapy.

Synaptic and intrinsic activation of GABAergic neurons in the cardiorespiratory brainstem network.

GABAergic pathways in the brainstem play an essential role in respiratory rhythmogenesis and interactions between the respiratory and cardiovascular neuronal control networks. However, little is known about the identity and function of these GABAergic inhibitory neurons and what determines their activity. In this study we have identified a population of GABAergic neurons in the ventrolateral medulla that receive increased excitatory post-synaptic potentials during inspiration, but also have spontaneous firing in the absence of synaptic input. Using transgenic mice that express GFP under the control of the Gad1 (GAD67) gene promoter, we determined that this population of GABAergic neurons is in close apposition to cardioinhibitory parasympathetic cardiac neurons in the nucleus ambiguus (NA). These neurons fire in synchronization with inspiratory activity. Although they receive excitatory glutamatergic synaptic inputs during inspiration, this excitatory neurotransmission was not altered by blocking nicotinic receptors, and many of these GABAergic neurons continue to fire after synaptic blockade. The spontaneous firing in these GABAergic neurons was not altered by the voltage-gated calcium channel blocker cadmium chloride that blocks both neurotransmission to these neurons and voltage-gated Ca(2+) currents, but spontaneous firing was diminished by riluzole, demonstrating a role of persistent sodium channels in the spontaneous firing in these cardiorespiratory GABAergic neurons that possess a pacemaker phenotype. The spontaneously firing GABAergic neurons identified in this study that increase their activity during inspiration would support respiratory rhythm generation if they acted primarily to inhibit post-inspiratory neurons and thereby release inspiration neurons to increase their activity. This population of inspiratory-modulated GABAergic neurons could also play a role in inhibiting neurons that are most active during expiration and provide a framework for respiratory sinus arrhythmia as there is an increase in heart rate during inspiration that occurs via inhibition of premotor parasympathetic cardioinhibitory neurons in the NA during inspiration.

Lack of efficacy of blueberry in nutritional prevention of azoxymethane-initiated cancers of rat small intestine and colon.

BACKGROUND: Blueberries may lower relative risk for cancers of the gastrointestinal tract. Previous work indicated an inhibitory effect of consumed blueberry (BB) on formation of aberrant crypt foci (ACF) in colons of male Fisher F344 rats (inbred strain). However, effects of BB on colon tumors and in both genders are unknown. METHODS: We examined efficacy of BB in inhibition of azoxymethane (AOM)-induced colon ACF and intestine tumors in male and female Sprague-Dawley rats (outbred strain). Pregnant rats were fed a diet with or without 10% BB powder; progeny were weaned to the same diet as their dam and received AOM as young adults. RESULTS: Male and female rats on control diet had similar numbers of ACF at 6 weeks after AOM administration. BB increased (P < 0.05) ACF numbers within the distal colon of female but not male rats. There was a significant (P < 0.05) diet by gender interaction with respect to total colon ACF number. Colon and duodenum tumor incidences were less in females than males at 17 weeks after AOM. BB tended (0.1 > P > 0.05) to reduce overall gastrointestinal tract tumor incidence in males, however, tumor incidence in females was unaffected (P > 0.1) by BB. There was a tendency (0.1 > P > 0.05) for fewer adenocarcinomas (relative to total of adenomatous polyps plus adenocarcinomas) in colons of female than male tumor-bearing rats; in small intestine, this gender difference was significant (P < 0.05). BB favored (P < 0.05) fewer adenocarcinomas and more adenomatous polyps (as a proportion of total tumor number) in female rat small intestine. CONCLUSION: Results did not indicate robust cancer-preventive effects of BB. Blueberry influenced ACF occurrence in distal colon and tumor progression in duodenum, in gender-specific fashion. Data indicate the potential for slowing tumor progression (adenomatous polyp to adenocarcinoma) by BB.

The role of 5-HT3 and other excitatory receptors in central cardiorespiratory responses to hypoxia: implications for sudden infant death syndrome.

Although brainstem serotonergic (5-HT) systems are involved in the protective responses to hypoxia, abnormalities of 5-HT function are strongly implicated in SIDS, and the neurochemical mechanisms by which 5-HT receptors influence brainstem cardiorespiratory responses to hypoxia remains unclear. This study focuses on the role of excitatory neurotransmission, including 5-HT3 signaling, to cardiac vagal neurons (CVNs) that dominate the control of heart rate. Excitatory synaptic inputs to CVNs, located in the nucleus ambiguus (NA), were recorded simultaneously with respiratory activity in in vitro brainstem slices. During control conditions excitatory inputs to CVNs were blocked by application of NMDA and AMPA/kainate glutamatergic receptor antagonists, whereas the 5-HT3 and purinergic receptor antagonists ondansetron and pyridoxal-phosphate-6-azophenyl-2',4'-disulfonic acid (PPADS), respectively, had no effect. However, during hypoxia ondansetron inhibited excitatory neurotransmission to CVNs. In recovery from hypoxia, spontaneous and respiratory-related excitatory events were blocked by glutamatergic and purinergic receptor blockers, respectively, whereas ondancetron had no effect. These results demonstrate that hypoxia recruits a 5-HT pathway to CVNs that activates 5-HT3 receptors on CVNs to maintain parasympathetic cardiac activity during hypoxia. Exaggeration of this 5-HT neurotransmission could increase the incidence of bradycardia and risk of sudden infant death during hypoxia.

A comparison of the binding profiles of dextromethorphan, memantine, fluoxetine and amitriptyline: treatment of involuntary emotional expression disorder.

We compared the binding profiles of medications potentially useful in the treatment of involuntary emotional expression disorder at twenty-six binding sites in rat brain tissue membranes. Sites were chosen based on likelihood of being target sites for the mechanism of action of the agents in treating the disorder or their likelihood in producing side effects experienced by patients treated with psychoactive agents. We used radioligand binding assays employing the most selective labeled ligands available for sites of interest. Concentrations of labeled ligand were used at or below the K(i) value of the ligand for the target site. Compounds were initially screened at 1 muM. For compounds that competed for greater than 20-30% of specific binding at target sites of interest, full concentration curves were constructed. Dextromethorphan, amitriptyline and fluoxetine competed for binding to sigma(1) receptors and to serotonin transporters with high to moderate affinity. Of the target sites tested, these are the most likely to contribute to the therapeutic benefit of the various agents. In addition, all three drugs showed some activity at alpha(2) and 5-HT(1B/D) sites. Of the drugs tested, dextromethorphan bound to the fewest sites unlikely to be target sites. Although the mechanism of action of dextromethorphan or any drug that has been used in the treatment of involuntary emotional expression disorder is currently unknown, our data support that the affinity of the drug for sigma(1) receptors is consistent with its possible action through this receptor type in controlling symptoms of the disorder.

A novel immune-to-CNS communication pathway: cells of the meninges surrounding the spinal cord CSF space produce proinflammatory cytokines in response to an inflammatory stimulus.

Pain is enhanced in response to elevations of proinflammatory cytokines in spinal cerebrospinal fluid (CSF), following either intrathecal injection of these cytokines or intrathecal immune challenge with HIV-1 gp120 that induces cytokine release. Spinal cord glia have been assumed to be the source of endogenous proinflammatory cytokines that enhance pain. However, assuming that spinal cord glia are the sole source of CSF cytokines may be an underestimate, as the cellular composition of the meninges surrounding the spinal cord CSF space includes several cell types known to produce proinflammatory cytokines. The present experiments provide the first investigation of the immunocompetent nature of the spinal cord meninges. Here, we explore whether rat meninges are responsive to intrathecal gp120. These studies demonstrate that: (a) intrathecal gp120 upregulates meningeal gene expression of proinflammatory signals, including tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), interleukin 6 (IL-6), and inducible nitric oxide synthase (iNOS), and (b) intrathecal gp120 induces meningeal release of TNF-alpha, IL-1beta, and IL-6. In addition, stimulation of isolated meninges in vitro with gp120 induced the release of TNF-alpha and IL-1beta, indicating that the resident cells of the meninges are able to respond without immune cell recruitment. Taken together, these data document that the meninges are responsive to immunogenic stimuli in the CSF and that the meninges may be a source of immune products detected in CSF. The ability of the meninges to release to proinflammatory signals suggests a potential role in the modulation of pain.

Norman Cousins Lecture. Glia as the "bad guys": implications for improving clinical pain control and the clinical utility of opioids.

Within the past decade, there has been increasing recognition that glia are far more than simply "housekeepers" for neurons. This review explores two recently recognized roles of glia (microglia and astrocytes) in: (a) creating and maintaining enhanced pain states such as neuropathic pain, and (b) compromising the efficacy of morphine and other opioids for pain control. While glia have little-to-no role in pain under basal conditions, pain is amplified when glia become activated, inducing the release of proinflammatory products, especially proinflammatory cytokines. How glia are triggered to become activated is a key issue, and appears to involve a number of neuron-to-glia signals including neuronal chemokines, neurotransmitters, and substances released by damaged, dying and dead neurons. In addition, glia become increasingly activated in response to repeated administration of opioids. Products of activated glia increase neuronal excitability via numerous mechanisms, including direct receptor-mediated actions, upregulation of excitatory amino acid receptor function, downregulation of GABA receptor function, and so on. These downstream effects of glial activation amplify pain, suppress acute opioid analgesia, contribute to the apparent loss of opioid analgesia upon repeated opioid administration (tolerance), and contribute to the development of opioid dependence. The potential implications of such glial regulation of pain and opioid actions are vast, suggestive that targeting glia and their proinflammatory products may provide a novel and effective therapy for controlling clinical pain syndromes and increasing the clinical utility of analgesic drugs.

Tumor-protective and tumor-promoting actions of dietary whey proteins in an N-methyl-N-nitrosourea model of rat mammary carcinogenesis.

The mammary tumor-protective effects of dietary factors are considered to be mediated by multiple signaling pathways, consistent with the heterogeneous nature of the disease and the distinct genetic profiles of tumors arising from diverse mammary cell populations. In a 7,12-dimethylbenz(a)anthracene-induced model of carcinogenesis, we showed previously that female Sprague-Dawley rats exposed to AIN-93G diet containing whey protein hydrolysate (WPH) beginning at gestation Day 4 had reduced tumor incidence than those exposed to diet containing casein (CAS), due partly to increased mammary differentiation and reduced activity of phase I metabolic enzymes. Here, we evaluated the tumor-protective effects of these same dietary proteins to the direct-acting carcinogen N-methyl-N-nitrosourea (NMU). We found that lifetime exposure to WPH, relative to CAS, decreased mammary tumor incidence and prolonged the appearance of tumors in NMU-treated female rats, with no corresponding effects on tumor multiplicity. At 115 days post-NMU, histologically normal mammary glands from WPH-fed tumor-bearing rats had increased gene expression for the tumor suppressor BRCA1 and the differentiation marker kappa-casein than those of CAS-fed tumor-bearing rats. Tumor-bearing rats from the WPH group had more advanced tumors, with a greater incidence of invasive ductal carcinoma than ductal carcinoma in situ and higher serum C-peptide levels than corresponding rats fed CAS. WPH-fed tumor-bearing rats were also heavier after NMU administration than CAS tumor-bearing rats, although no correlation was noted between body weight and C-peptide levels for either diet group. Results demonstrate the context-dependent tumor-protective and tumor-promoting effects of WPH; provide support for distinct signaling pathways underlying dietary effects on development of mammary carcinoma; and raise provocative questions on the role of diet in altering the prognosis of existing breast tumors.

In vitro regulation of serotonin transporter activity by protein kinase A and nicotinic acetylcholine receptors in the prefrontal cortex of rats.

We investigated the effect of in vitro exposure to nicotinic acetylcholine receptors (nAChRs), agonists, antagonists, and protein kinase A (PKA) modulators on the activity of the serotonin transporter (SERT) in prefrontocortical (PFC) synaptosomes. The plasma membrane SERT is an active transport mechanism specific for serotonin. Receptors and second messengers capable of altering transporter activity would be expected to have profound effects on serotonergic neurotransmission and on functions involving serotonergic input, such as cognition, anxiety, and mood. Our data suggest that activation of nAChRs, quite likely via PKA, increase the activity of the SERT in the PFC and, thereby, can alter 5-HT levels in a region important in the behavioral effects of nicotine and 5-HT. Nicotine at 4 microM increased [(3)H]5-HT uptake by 75%. Because the nAChR antagonists mecamylamine and dihydro-beta-erythrodine (DHbetaE) both decreased [(3)H]5-HT uptake into synaptosomes, it appeared that the SERT might be tonically activated by acetylcholine present within our synaptosomal preparations. Blocking PKA significantly decreased [(3)H]5-HT, while stimulation of PKA activity significantly increased the uptake. A 66% decrease compared with control was produced by 100 microM Rp-cAMP, and a 41% increase in 5-HT uptake over control was observed with 30 microM Sp-cAMPs. Furthermore, the enhancement in uptake produced by 4 microM nicotine was inhibited in a time-dependent fashion by preincubation with 10 microM Rp-cAMP. A better understanding of the influence of the cholinergic system and the receptors involved in the trafficking of SERT would help clarify the important relationship between the cholinergic and serotonergic systems and the role these systems play in behavior.

Rapid isolation of highly enriched and quiescent microglia from adult rat hippocampus: immunophenotypic and functional characteristics.

Isolation of microglia from CNS tissue provides a powerful tool to study basic microglia biology and examine the effects of in vivo treatments on microglia immunophenotype and function. Previous microglia isolation methodologies utilized whole brain. However, microglia immunophenotype varies across CNS anatomical loci, thus isolation of microglia from whole brain may obscure regional brain variations in microglia immunophenotype and function. In addition, it is unknown to what extent microglia isolation procedures alter the in situ immunophenotype and function of microglia. The present report details a procedure for the rapid isolation of microglia from discrete CNS anatomical loci and addresses the issue of whether the in situ microglia immunophenotype is significantly altered by the isolation procedure. The present microglia isolation method yielded highly enriched hippocampal microglia, which were devoid of other CNS macrophage subtypes and exhibited attributes reflecting a quiescent phenotype characteristic of microglia observed in situ under non-pathological conditions. Further, isolated microglia exhibited functional responsiveness to immunogenic stimuli ex vivo. The immunophenotypic and functional attributes of isolated microglia suggest that the isolation procedure preserves the in vivo phenotype of microglia, thus providing an experimental method with minimal procedural confounds for examining in vivo treatments on microglia ex vivo.

Serial reversal learning of position discrimination in developing rats.

The current study established a procedure to evaluate the capability of rats on postnatal days (PND) 21, 26, and 30 to perform a spatial serial reversal task using a T-maze. Training consisted of an acquisition session followed by a series of six reversal sessions. To examine the role of proactive interference in the serial reversal effect, the point of reversal was manipulated so that it occurred at the start of each session (between-sessions) or the midpoint of each session (within-sessions). Performance was initially impaired during the first reversal but improved dramatically across the series. Reversal between-sessions enhanced this serial reversal effect in comparison to reversal within-sessions. Experiment 1 showed that rats of all ages learned the between-sessions serial reversal task at a comparable rate. However, on the within-sessions task, PND21 rats were impaired relative to the PND26 and 30 rats, which did not differ. Experiment 2 revealed that the addition of a tactile cue that is correlated with each phase of reversal eliminated age and task differences in serial reversal performance. These findings suggest that higher-order cognitive processes underlying serial reversal are present during the weanling period, but there is some improvement with age under conditions involving high memory interference and/or difficulty in detecting the transition between reversal phases.

Central proinflammatory cytokines and pain enhancement.

Enhanced pain is a component of the 'sickness response' which is an evolutionarily adaptive constellation of responses that enhance the survival of the host. Proinflammatory cytokines mediate these sickness behaviors, and whether proinflammatory cytokines are involved in exaggerated pain has become an intriguing question. Studies suggest that spinal cord glial cells (astrocytes and microglia) are activated in conditions that lead to enhanced pain. Not only is glial activation associated with enhanced pain, but it is also integral to the induction and maintenance of these pain states. Proinflammatory cytokines can be released by activated astrocytes and microglia within the central nervous system. This review will discuss the role of proinflammatory cytokines in experimental models of prolonged pain states. Administration of exogenous proinflammatory cytokines facilitates pain, and agents that antagonize proinflammatory cytokine actions have been shown to block and/or reverse enhanced pain. These findings suggest that blocking the synthesis and/or release of proinflammatory cytokines may be viable strategies for the treatment of pathological pain. Gene therapy to augment the endogenous anti-inflammatory cytokine, interleukin-10, is one of the more promising therapies currently under study.

Controlling pathological pain by adenovirally driven spinal production of the anti-inflammatory cytokine, interleukin-10.

Gene therapy for the control of pain has, to date, targeted neurons. However, recent evidence supports that spinal cord glia are critical to the creation and maintenance of pain facilitation through the release of proinflammatory cytokines. Because of the ability of interleukin-10 (IL-10) to suppress proinflammatory cytokines, we tested whether an adenoviral vector encoding human IL-10 (AD-h-IL10) would block and reverse pain facilitation. Three pain models were examined, all of which are mediated by spinal pro-inflammatory cytokines. Acute intrathecal administration of rat IL-10 protein itself briefly reversed chronic constriction injury-induced mechanical allodynia and thermal hyperalgesia. The transient reversal caused by IL-10 protein paralleled the half-life of human IL-10 protein in the intrathecal space (t(1/2) approximately 2 h). IL-10 gene therapy both prevented and reversed thermal hyperalgesia and mechanical allodynia, without affecting basal responses to thermal or mechanical stimuli. Extra-territorial, as well as territorial, pain changes were reversed by this treatment. Intrathecal AD-h-IL10 injected over lumbosacral spinal cord led to elevated lumbosacral cerebrospinal fluid (CSF) levels of human IL-10, with far less human IL-10 observed in cervical CSF. In keeping with IL-10's known anti-inflammatory actions, AD-h-IL10 lowered CSF levels of IL-1, relative to control AD. These studies support that this gene therapy approach provides an alternative to neuronally focused drug and gene therapies for clinical pain control.

Controlling neuropathic pain by adeno-associated virus driven production of the anti-inflammatory cytokine, interleukin-10.

Despite many decades of drug development, effective therapies for neuropathic pain remain elusive. The recent recognition of spinal cord glia and glial pro-inflammatory cytokines as important contributors to neuropathic pain suggests an alternative therapeutic strategy; that is, targeting glial activation or its downstream consequences. While several glial-selective drugs have been successful in controlling neuropathic pain in animal models, none are optimal for human use. Thus the aim of the present studies was to explore a novel approach for controlling neuropathic pain. Here, an adeno-associated viral (serotype II; AAV2) vector was created that encodes the anti-inflammatory cytokine, interleukin-10 (IL-10). This anti-inflammatory cytokine is known to suppress the production of pro-inflammatory cytokines. Upon intrathecal administration, this novel AAV2-IL-10 vector was successful in transiently preventing and reversing neuropathic pain. Intrathecal administration of an AAV2 vector encoding beta-galactosidase revealed that AAV2 preferentially infects meningeal cells surrounding the CSF space. Taken together, these data provide initial support that intrathecal gene therapy to drive the production of IL-10 may prove to be an efficacious treatment for neuropathic pain.