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Background The oral microbiota has been implicated in the pathogenesis of rheumatoid arthritis through activation of mucosal immunity. This study tested for associations between oral health, microbial communities and juvenile idiopathic arthritis (JIA). Methods A cross-sectional exploratory study of subjects aged 10–18 years with oligoarticular, extended oligoarticular and polyarticular JIA was conducted. Control groups included pediatric dental clinic patients and healthy volunteers. The primary aim was to test for an association between dental health indices and JIA; the secondary aim was to characterize the microbial profile of supragingival plaque using 16S rRNA gene sequencing. Results The study included 85 patients with JIA, 62 dental patients and 11 healthy child controls. JIA patients overall had significantly more gingival inflammation compared to dental patients, as evidenced by bleeding on probing of the gingiva, the most specific sign of active inflammation (p = 0.02). Overall, however, there was a trend towards better dental hygiene in the JIA patients compared to dental patients, based on indices for plaque, decay, and periodontitis. In the JIA patients, plaque microbiota analysis revealed bacteria belonging to genera Haemophilus or Kingella elevated, and Corynebacterium underrepresented. In poly JIA, bacteria belonging to the genus Porphyromonas was overrepresented and Prevotella was underrepresented. Conclusion Increased gingival inflammation in JIA was independent of general oral health, and thus cannot be attributed to poor dental hygiene secondary to disability. The variation of microbial profile in JIA patients could indicate a possible link between gingivitis and synovial inflammation.

Objectives The primary objective of this study was to evaluate the safety and tolerability of a formulated IL-12 plasmid administered intraperitoneally (IP) in conjunction with intravenous (IV) carboplatin/docetaxel in platinum-sensitive ovarian cancer patients. Methods Escalating doses of IL-12 plasmid (phIL-12) formulated with the lipopolymer PEG-PEI-Cholesterol (PPC) were administered IP every 10–11 days for a total of four treatments and the highest dose was expanded to eight treatments. Patients also received IV carboplatin (AUC 5) and docetaxel (75 mg/m2) every 21 days. Patients were followed for safety, biological activity and antitumor activity after phIL-12/PPC treatment. Results All 13 patients enrolled in the study received both phIL-12/PPC and chemotherapy treatment. There were 49 plasmid-associated adverse events (AEs). The most common AEs were abdominal pain, transient hypotension, low grade fever, catheter site pain, chills, dysgeusia, infusion-related reaction, and nausea. These AEs appeared to be plasmid dose related. Grade 3 AEs included manageable abdominal pain and cytokine release syndrome. There were no dose limiting toxicities and the plasmid treatment did not augment the chemotherapy-associated AEs. The best overall antitumor response (17% CR, 33% PR, 42% SD and 8% PD) was typical of the patient population enrolled for the study. Translational studies showed rise in IFN-γ and TNF-α concentrations in a dose dependent manner. Conclusions The escalating doses and cycles of intraperitoneal phIL-12/PPC when combined with carboplatin/docetaxel chemotherapy in recurrent ovarian cancer patients were well tolerated and did not appear to exacerbate the side effects or attenuate the efficacy of the chemotherapy treatment.

Brain-derived neurotrophic factor has been associated previously with the regulation of food intake. To help elucidate the role of this neurotrophin in weight regulation, we have generated conditional mutants in which brain-derived neurotrophic factor has been eliminated from the brain after birth through the use of the cre-loxP recombination system. Brain-derived neurotrophic factor conditional mutants were hyperactive after exposure to stressors and had higher levels of anxiety when evaluated in the light/dark exploration test. They also had mature onset obesity characterized by a dramatic 80–150% increase in body weight, increased linear growth, and elevated serum levels of leptin, insulin, glucose, and cholesterol. In addition, the mutants had an abnormal starvation response and elevated basal levels of POMC, an anorexigenic factor and the precursor forα -MSH. Our results demonstrate that brain derived neurotrophic factor has an essential maintenance function in the regulation of anxiety-related behavior and in food intake through central mediators in both the basal and fasted state.

Recent evidence suggests that neuropeptide Y (NPY), originating in neurons in the hypothalamic arcuate nucleus, is an important mediator of the effects of leptin on the central nervous system. As these NPY neurons innervate hypophysiotropic neurons in the hypothalamic paraventricular nucleus (PVN) that produce the tripeptide, TRH, we raised the possibility that NPY may be responsible for resetting of the hypothalamic-pituitary-thyroid (HPT) axis during fasting. To test this hypothesis, the effects of intracerebroventricularly administered NPY on circulating thyroid hormone levels and proTRH messenger RNA in the PVN were studied by RIA and in situ hybridization histochemistry, respectively. NPY administration suppressed circulating levels of thyroid hormone (T(3) and T(4)) and resulted in an inappropriately normal or low TSH. These alterations were associated with a significant suppression of proTRH messenger RNA in the PVN, indicating that NPY infusion had resulted in a state of central hypothyroidism. Similar observations were made in NPY-infused animals pair fed to the vehicle-treated controls. These data are reminiscent of the effect of fasting on the thyroid axis and indicate that NPY may play a major role in the inhibition of HPT axis during fasting.

Leptin has profound effects on food intake, body weight, and neuroendocrine status. The lack of leptin results in hormonal and metabolic alterations and a dramatic increase in body weight. Leptin acts in the brain, especially in the hypothalamus; however, the central nervous system sites that respond to leptin have not been examined comprehensively. In this study, we explored systematically the distribution of leptin-activated neurons throughout the rat brain. Furthermore, we investigated the chemical identity of subsets of these leptin-activated cells. Fos-like immunoreactivity (Fos-IR) was investigated in the rat brain after two different doses of leptin (1.0 mg/kg and 5.0 mg/kg) at 2 hours and 6 hours after injections. The induction of Fos-IR was observed in hypothalamic nuclei, including the paraventricular nucleus (PVH), the retrochiasmatic area (RCA), the ventromedial nucleus (VMH), the dorsomedial nucleus (DMH), the arcuate nucleus (Arc), and the ventral premammillary nucleus (PMV). In addition, leptin-induced Fos-IR was found in several nuclei of the brainstem, including the superior lateral and external lateral subdivisions of the parabrachial nucleus (slPB and elPB, respectively), the supragenual nucleus, and the nucleus of the solitary tract (NTS). By using double-labeling immunohistochemistry or immunohistochemistry coupled with in situ hybridization, leptin-activated neurons were found that contained cocaine- and amphetamine-regulated transcript mRNA in several hypothalamic nuclei, including the RCA, Arc, DMH, and PMV. In the Arc and DMH, leptin-induced Fos-IR was observed in neurons that expressed neurotensin mRNA. Dynorphin neurons in the VMH and in the Arc also expressed Fos-IR. In the brainstem, we found that cholecystokinin neurons in the slPB and glucagon-like peptide-1 neurons in the NTS were activated by leptin. We also investigated the coexpression of Fos-IR and the long form of the leptin receptor (OBRb) mRNA. We found double-labeled neurons surrounding the median eminence and in the RCA, Arc, VMH, DMH, and PMV. However, in brainstem sites, very little OBRb mRNA was found; thus, there were very few double-labeled cells. These results suggest that leptin stimulates brain pathways containing neuropeptides that are involved in the regulation of energy balance, autonomic homeostasis, and neuroendocrine status.

The action of prostaglandin E(2) (PGE(2)) in the preoptic area is thought to play an important role in producing fever. Pharmacologic evidence suggests that, among the four subtypes of E-series prostaglandin (EP) receptors, i.e., EP(1), EP(2), EP(3), and EP(4), the EP(1) receptor mediates fever responses. In contrast, evidence from mice with EP receptor gene deletions indicates that the EP(3) receptor is required for the initial (

Recent studies have reinforced the view that the lateral hypothalamic area (LHA) regulates food intake and body weight. We identified leptin-sensitive neurons in the arcuate nucleus of the hypothalamus (Arc) that innervate the LHA using retrograde tracing with leptin administration. We found that retrogradely labeled cells in the Arc contained neuropeptide Y (NPY) mRNA or proopiomelanocortin (POMC) mRNA. Following leptin administration, NPY cells in the Arc did not express Fos but expressed suppressor of cytokine signaling-3 (SOCS-3) mRNA. In contrast, leptin induced both Fos and SOCS-3 expression in POMC neurons, many of which also innervated the LHA. These findings suggest that leptin directly and differentially engages NPY and POMC neurons that project to the LHA, linking circulating leptin and neurons that regulate feeding behavior and body weight homeostasis.

Ciliary neurotrophic factor (CNTF) is a neurocytokine expressed in glial cells that acts on brain cells to promote gene expression, survival, and differentiation. When administered systemically, CNTF reduces food intake and body weight in rodents. Genes encoding suppressors of cytokine signaling (SOCS) are induced by cytokines that activate membrane receptors in the same class as those that are activated by CNTF. We therefore examined the ability of CNTF to induce expression of socs genes in brain and peripheral tissues of rats and mice. Peripheral CNTF administration to ob/ob mice rapidly induced SOCS-3 messenger RNA (mRNA) in hypothalamus, as determined by Northern blotting and quantitative RT-PCR, but had no effect on cytokine-inducible sequence (CIS), SOCS-1, or SOCS-2 mRNA. In situ hybridization histochemistry of hypothalamus from ob/ob mice and normal rats demonstrated that CNTF induced SOCS-3 mRNA in the arcuate nucleus (Arc). Strong hybridization signals were also detected in the ependymal lining of the ventricles and the subfornical organ. This hybridization pattern was distinct from that resulting from peripheral leptin treatment with overlapping hybridization patterns only in the Arc. CNTF also induced expression of CIS, SOCS-1, SOCS-2, and SOCS-3 mRNA in the liver, and SOCS-2 and SOCS-3 mRNA in the kidney. CNTF induced SOCS-3 mRNA and SOCS-3 protein levels in an astrocyte cell line. Transient expression of SOCS-3, but not CIS or SOCS-2, inhibited CNTF-induced signal transduction in astrocytes. In conclusion, SOCS-3 mRNA is specifically induced by CNTF in regions of the hypothalamus that are both overlapping and distinct from that induced by leptin. Similar to leptin, the Arc is likely to be a direct target of CNTF, and this region may play a role in the body weight-reducing effects of CNTF. SOCS-3 is a negative regulator of CNTF signal transduction, and inhibitors of SOCS-3 function may enhance endogenous CNTF signaling after neuronal injury or enhance the body weight-reducing effect of CNTF after peripheral administration.

Recent studies have identified several neuropeptide systems in the hypothalamus that are critical in the regulation of body weight. The lateral hypothalamic area (LHA) has long been considered essential in regulating food intake and body weight. Two neuropeptides, melanin-concentrating hormone (MCH) and the orexins (ORX), are localized in the LHA and provide diffuse innervation of the neuraxis, including monosynaptic projections to the cerebral cortex and autonomic preganglionic neurons. Therefore, MCH and ORX neurons may regulate both cognitive and autonomic aspects of food intake and body weight regulation. The arcuate nucleus also is critical in the regulation of body weight, because it contains neurons that express leptin receptors, neuropeptide Y (NPY), alpha-melanin-stimulating hormone (alpha-MSH), and agouti-related peptide (AgRP). In this study, we examined the relationships of these peptidergic systems by using dual-label immunohistochemistry or in situ hybridization in rat, mouse, and human brains. In the normal rat, mouse, and human brain, ORX and MCH neurons make up segregated populations. In addition, we found that AgRP- and NPY-immunoreactive neurons are present in the medial division of the human arcuate nucleus, whereas alpha-MSH-immunoreactive neurons are found in the lateral arcuate nucleus. In humans, AgRP projections were widespread in the hypothalamus, but they were especially dense in the paraventricular nucleus and the perifornical area. Moreover, in both rat and human, MCH and ORX neurons receive innervation from NPY-, AgRP-, and alpha-MSH-immunoreactive fibers. Projections from populations of leptin-responsive neurons in the mediobasal hypothalamus to MCH and ORX cells in the LHA may link peripheral metabolic cues with the cortical mantle and may play a critical role in the regulation of feeding behavior and body weight.

The adipocyte-derived hormone leptin decreases body weight in part by activating the sympathetic nervous system, resulting in increased thermogenesis and energy expenditure. We investigated hypothalamic pathways underlying leptin’s effects on stimulating the sympathetic nervous system. We found that leptin activates neurons in the retrochiasmatic area (RCA) and lateral arcuate nucleus (Arc) that innervate the thoracic spinal cord and also contain cocaine- and amphetamine-regulated transcript (CART). We also found that most CART-containing neurons in the RCA and Arc of the hypothalamus also contain proopiomelanocortin (POMC) mRNA. The finding that leptin activates CART/POMC neurons innervating sympathetic preganglionic neurons in the thoracic spinal cord suggests that this pathway may contribute to the increased thermogenesis and energy expenditure and decreased body weight observed following leptin administration.

Ciliary neurotrophic factor (CNTF) and leptin decrease food intake and body weight. Lipopolysaccharide (LPS) is a potent exogenous pyrogen and produces anorexia via cytokine production. CNTF-, leptin-, and LPS-induced cytokines all act on type I cytokine receptors. However, it is not known if these cytokines engage similar central nervous system (CNS) pathways to exert their effects. To assess mechanisms by which these cytokines act, we examined the patterns of immediate early gene expression (SOCS-3, c-fos, and tis-11) in the brain following intravenous administration. CNTF and LPS induced gene expression in circumventricular organs; ependymal cells of the ventricles, meninges, and choroid plexus; and the arcuate nucleus of the hypothalamus. CNTF administration also induced fever and cyclooxygenase-2 mRNA expression. In contrast, we found no evidence of leptin-induced inflammation. CNTF and leptin are being assessed as potential therapeutic antiobesity agents, and both potently reduce food intake. Our findings support the hypothesis that CNTF and leptin engage distinct CNS sites and CNTF possesses inflammatory properties distinct from leptin.

Cocaine- and amphetamine-regulated transcript (CART) is a recently described neuropeptide widely expressed in the rat brain. CART mRNA and peptides are found in hypothalamic sites such as the paraventricular nucleus (PVH), the supraoptic nucleus (SON), the lateral hypothalamic area (LHA), the dorsomedial nucleus of the hypothalamus (DMH), the arcuate nucleus (Arc), the periventricular nucleus (Pe), and the ventral premammillary nucleus (PMV). Intracerebroventricular administration of recombinant CART peptide decreases food intake and CART mRNA levels in the Arc are regulated by leptin. Leptin administration induces Fos expression in hypothalamic CART neurons in the PVH, the DMH, the Arc, and the PMV. In the current study, we used double label in situ hybridization histochemistry to investigate the potential direct action of leptin on hypothalamic CART neurons and to define the chemical identity of the hypothalamic CART neurons in the rat brain. We found that CART neurons in the Arc, DMH, and PMV express long form leptin-receptor mRNA, and the suppressor of cytokine signaling-3 (SOCS-3) mRNA after an acute dose of intravenous leptin. We also found that CART neurons in the parvicellular PVH, in the DMH and in the posterior Pe coexpress thyrotropin-releasing hormone (TRH) mRNA. CART neurons in the magnocellular PVH and in the SON coexpress dynorphin (DYN), and CART cell bodies in the LHA and in the posterior Pe coexpress melanin-concentrating hormone (MCH) and glutamic acid decarboxylase (GAD-67) mRNA. In the Arc, a few CART neurons coexpress neurotensin (NT) mRNA. In addition, we examined the distribution of CART immunoreactivity in the human hypothalamus. We found CART cell bodies in the PVH, in the SON, in the LHA, in the Arc (infundibular nucleus) and in the DMH. We also observed CART fibers throughout the hypothalamus, in the bed nucleus of the stria terminalis, and in the amygdala. Our results indicate that leptin directly acts on CART neurons in distinct nuclei of the rat hypothalamus. Furthermore, hypothalamic CART neurons coexpress neuropeptides involved in energy homeostasis, including MCH, TRH, DYN, and NT. The distribution of CART cell bodies and fibers in the human hypothalamus indicates that CART may also play a role in the regulation of energy homeostasis in humans.

Because cocaine- and amphetamine-regulated transcript (CART) coexists with α-melanocyte stimulating hormone (α-MSH) in the arcuate nucleus neurons and we have recently demonstrated that α-MSH innervates TRH-synthesizing neurons in the hypothalamic paraventricular nucleus (PVN), we raised the possibility that CART may also be contained in fibers that innervate hypophysiotropic thyrotropin-releasing hormone (TRH) neurons and modulate TRH gene expression. Triple-labeling fluorescentin situhybridization and immunofluorescence were performed to reveal the morphological relationships between pro-TRH mRNA-containing neurons and CART- and α-MSH-immunoreactive (IR) axons. CART-IR axons densely innervated the majority of pro-TRH mRNA-containing neurons in all parvocellular subdivisions of the PVN and established asymmetric synaptic specializations with pro-TRH neurons. However, whereas all α-MSH-IR axons in the PVN contained CART-IR, only a portion of CART-IR axons in contact with pro-TRH neurons were immunoreactive for α-MSH. In the medial and periventricular parvocellular subdivisions of the PVN, CART was co-contained in ∼80% of pro-TRH neuronal perikarya, whereas colocalization with pro-TRH was found in 80% of TRH/CART neurons in the periventricular and medial parvocellular subdivisions accumulated Fluoro-Gold after systemic administration, suggesting that CART may serve as a marker for hypophysiotropic TRH neurons. CART prevented fasting-induced suppression of pro-TRH in the PVN when administered intracerebroventricularly and increased the content of TRH in hypothalamic cell cultures. These studies establish an anatomical association between CART and pro-TRH-producing neurons in the PVN and demonstrate that CART has a stimulatory effect on hypophysiotropic TRH neurons by increasing pro-TRH gene expression and the biosynthesis of TRH.

Knife cuts ventral or medial to the striatum were used to interrupt some of the principal connections of this structure. All of the cuts depleted striatal dopamine and produced aphagia and adipsia but there was no indication that the two classes of effects were always correlated. Cuts medial to the striatum produced the most severe DA depletions, persistent aphagia and adipsia, and the full complement of deficits in responding to glucoprivic and hydrational challenges that characterize rats that have recovered from lateral hypothalamic lesions. Cuts ventral to posterior portions of the striatum produced comparable periods of aphagia and adipsia (but few of the persisting impairments in responsiveness to regulatory challenges) even though their effect on striatal DA was relatively small (the average depletion was 51% compared to 89% for rats with cuts medial to the striatum). A second group of rats with cuts below more anterior aspects of the striatum sustained severe DA depletions (70%) but only very brief periods of aphagia and adipsia and only slight deficits in responding to osmotic challenges. The effects of the DA depleting cuts were compared with the behavioral consequences of coronal cuts in the midbrain tegmentum which selectively depleted hypothalamic norepinephrine. These cuts did not produce reliable effects on either food or water intake but abolished the normal feeding response to 2-deoxy-d-glucose without affecting the response to insulin. A correlational analysis of the biochemical and behavioral results of our cuts indicated a significant positive relationship between drinking in response to cellular thirst stimuli and hypothalamic NE as well as striatal DA. The postoperative body weights of our experimental animals were positively correlated with striatal dopamine and negatively related to hypothalamic norepinephrine.

Parasagittal knife cuts along the lateral border of the diencephalon (PS), coronal cuts accross the lateral (LMFB) or medial (MMFB) components of the medial forebrain bundle reproduce most of the persisting deficits in responding to glucoprivic and hydrational challenges that characterize rats with lateral hypothalamic lesions or intracranial injections of 6-hydroxydopamine (60HDA). Each of these cuts produced a different pattern of regulatory deficits, suggesting that individual components of the LH syndrome may be mediated by different neural substrates. This interpretation is supported by the results of our correlational analysis of the relationships between specific behavioral and biochemical effects of our cuts. For example, feeding responses to insulin were reliably correlated with striatal DA concentrations but feeding responses to 2-deoxy-d-glucose (2DG) were not. Water intake during periods of food deprivation was reliably correlated with striatal DA but water intake after an experimental osmotic challenge was not. Only one of the common persisting deficits (impaired feeding response to peripheral injections of insulin) was positively correlated with the duration of aphagia and adipsia.

Aphagia and adipsia of equivalent duration were produced by knife cuts along the lateral border of the hypothalamus (PH cuts), or the medial surface of the globus pallidus (MP cuts) in male albino rats. Striatal dopamine (DA) was reduced by 75% in animals with PH cuts but only 50% by MP cuts. Hypothalamic norepinephrine was reduced 25% by PH cuts and was unaffected by MP cuts. Aphagia and adipsia were positively correlated with DA depletions only in rats with PH cuts. Presurgical catecholamine depletions produced by chronic injections of alpha-methyl-p-tyrosine did not alter the duration of aphagia or adipsia resulting from these knife cuts. However, following recovery of ingestive behavior, rats with PH and MP cuts were supersensitive to the anorexic effects of the dopamine-beta-hydroxylase inhibitor, diethyldithiocarbamate. Exaggerated anorexia was also observed after DA blockade by haloperidol or alpha-adrenergic blockade by phenoxybenzamine. The most pronounced effects of catecholamine blockade were observed in rats with PH cuts.

The raphe-spinal pathway, which contains co-localized serotonin (5-HT), thyrotropin-releasing hormone (TRH), and several TRH-prohormone-derived non-TRH peptides, projects to the ventral horn of the spinal cord. Pharmacologic ablation of this pathway with the 5-HT neurotoxin, 5, 7-dihydroxytryptamine, in neonatal rats resulted in deficient recovery of plantar foot muscles, functionally denervated with botulinum toxin type A. Failure of reinnervation was suggested by slower and incomplete recovery of the plantar foot compound muscle action potential amplitude and by a reduced mean diameter of plantar foot muscle fibers in ablated rats. These findings indicate that deprivation of alpha motor neurons from descending raphe-spinal input interferes with their ability to respond to muscle-derived signals for reinnervation.