Anti-Hyperuricemia Activity and Potential Mechanisms of Medicinal Mushroom Activity: A Review of Preclinical Studies.

Hyperuricemia (HUA) is characterized by abnormally elevated levels of serum uric acid, the product of purine metabolism. The primary symptom of HUA is gout; however, asymptomatic HUA is associated with complications such as hypertension, kidney disease, cardiovascular disease, and metabolic syndrome. The activation of xanthine oxidase (XO), a pivotal enzyme in uric acid biosynthesis, is coupled with extensive reactive oxygen species generation, leading to inflammatory responses, and triggers the development of HUA and its complications.

Oral Citrulline Mitigates Inflammation and Jejunal Damage via the Inactivation of Neuronal Nitric Oxide Synthase and Nuclear Factor-κB in Intestinal Ischemia and Reperfusion.

Background: Intestinal ischemia and reperfusion (I/R) is a life-threatening emergency accompanied by inflammation and organ damage. We compared the mechanisms and the effects of arginine, citrulline, and glutamine on inflammation and intestinal damage.

Materials And Methods: Male Wistar rats underwent 60 minutes of superior mesenteric artery occlusion and either 3 (I/R3) or 24 (I/R24) hours of reperfusion and were orally administered vehicle, arginine, citrulline, or glutamine 15 minutes before reperfusion and at 3, 9, and 21 hours of reperfusion.

[Three-dimensional vertically aligned CNTs coated by Ag nanoparticles for surface-enhanced Raman scattering].

In order to make surface-enhanced Raman scattering (SERS) substrates contained more "hot spots" in a three-dimensional (3D) focal volume, and can be adsorbed more probe molecules and metal nanoparticles, to obtain stronger Raman spectral signal, a new structure based on vertically aligned carbon nanotubes (CNTs) coated by Ag nanoparticles for surface Raman enhancement is presented. The vertically aligned CNTs are synthesized by chemical vapor deposition (CVD). A silver film is first deposited on the vertically aligned CNTs by magnetron sputtering.

Maturation of glutamatergic transmission in the vestibulo-olivary pathway impacts on the registration of head rotational signals in the brainstem of rats.

The recognition of head orientation in the adult involves multi-level integration of inputs within the central vestibular circuitry. How the different inputs are recruited during postnatal development remains unclear. We hypothesize that glutamatergic transmission at the vestibular nucleus contributes to developmental registration of head orientations along the vestibulo-olivary pathway.

Development of neural correlates of linear motion in the rat vestibular nucleus.

The capability of the central vestibular system in utilizing cues arising from the inner ear determines the ability of animals to acquire the sense of head orientations in the three-dimensional space and to shape postural movements. During development, neurons in the vestibular nucleus (VN) show significant changes in their electrophysiological properties. An age-dependent enhancement of membrane excitability is accompanied by a progressive increase in firing rate and discharge regularity.

Microchannel-based surface-enhanced Raman spectroscopy for integrated microfluidic analysis.

We have demonstrated a microchannel-based, surface-enhanced Raman spectroscopy (SERS) sensing approach for integrated microfluidic analysis developed using standard micro-fabrication technology. Our approach allows high-sensitivity SERS sensing with a comparatively low-excitation optical power intensity and large cross-sectional microchannel for biological cell analysis. Utilizing a microchannel with a cross section of 100 × 70 μm(2), we achieved a detection limit smaller than 10 nM for rhodamine 6G at an excitation power intensity of 132 W/cm(2), avoiding any possible heating effects on the sample under investigation.

Topography of inferior olivary neurons that encode canal and otolith inputs.

Vestibular information arising from rotational head movement and that from translational head movement are detected respectively by the semicircular canal and otolith organ in the inner ear. Spatiotemporal cues are in turn processed by the vestibulo-olivo-cerebellar pathway for sensorimotor coordination, but the role of the inferior olive (IO) in this pathway remains unclear. To address whether rotational and translational movements are differentially represented in the IO, we studied the distribution pattern of IO neurons recruited into the circuitry following selective activation of receptor hair cells of the horizontal semicircular canal or the utricle in adult rats.

Postnatal expression of TrkB receptor in rat vestibular nuclear neurons responsive to horizontal and vertical linear accelerations.

We examined the maturation expression profile of tyrosine kinase B (TrkB) receptor in rat vestibular nuclear neurons that were activated by sinusoidal linear acceleration along the horizontal or vertical axis. The otolithic origin of Fos expression in these neurons was confirmed with labyrinthectomized controls and normal controls, which showed only sporadically scattered Fos-labeled neurons in the vestibular nucleus. In P4-6 test rats, no Fos-labeled neurons were found in the vestibular nucleus, but the medial and spinal vestibular neurons showed weak immunoreactivity for TrkB.

Maturation profile of inferior olivary neurons expressing ionotropic glutamate receptors in rats: role in coding linear accelerations.

Using sinusoidal oscillations of linear acceleration along both the horizontal and vertical planes to stimulate otolith organs in the inner ear, we charted the postnatal time at which responsive neurons in the rat inferior olive (IO) first showed Fos expression, an indicator of neuronal recruitment into the otolith circuit. Neurons in subnucleus dorsomedial cell column (DMCC) were activated by vertical stimulation as early as P9 and by horizontal (interaural) stimulation as early as P11. By P13, neurons in the β subnucleus of IO (IOβ) became responsive to horizontal stimulation along the interaural and antero-posterior directions.

28-day oral safety evaluation of extracellular polysaccharopeptides produced in submerged culture from the turkey tail medicinal mushroom Trametes versicolor (L.:Fr.) Pilát LH-1 in mice.

Turkey tail medicinal mushroom, Trametes versicolor (TV), is a species with a variety of pharmacological activities. Its intracellular polysaccharopeptides are widely commercialized. Recently, we found a novel TV strain LH-1 in Taiwan and demonstrated that the extracellular polysaccharopeptide (ePSP) of LH-1 obtained from submerged culture exhibits significant immunomodulatory activity.

Maturation of canal-related brainstem neurons in the detection of horizontal angular acceleration in rats.

We examined the functional maturation of canal-related brainstem neurons in Sprague-Dawley rats at postnatal day (P)1 to adult. Conscious animals were subjected to cycles of angular acceleration and deceleration so as to selectively activate hair cells of the horizontal semicircular canals. Brainstem neurons were monitored for c-fos expression by immuno-hybridization histochemistry as an indicator of neuronal activation.

Developmental distribution of vestibular nuclear neurons responsive to different speeds of horizontal translation.

To examine whether subgroups of vestibular nuclear neurons encode different frequency oscillation of horizontal linear motion, Fos immunohistochemistry was used to document neuronal subpopulations that were functionally activated by such otolithic stimulations. Conscious rats at P7, P14 and adult were subjected to sinusoidal linear acceleration along the transverse axis on the horizontal plane. Labyrinthectomized and/or stationary controls showed only sporadically scattered Fos-labeled neurons in the vestibular nuclei, confirming otolithic origin of c-fos expression.

[Neuronal plasticity of otolith-related vestibular system].

This review focuses on our effort in addressing the development and lesion-induced plasticity of the gravity sensing system. After severance of sensory input from one inner ear, there is a bilateral imbalance in response dynamics and spatial coding behavior between neuronal subpopulations on the two sides. These data provide the basis for deranged spatial coding and motor deficits accompanying unilateral labyrinthectomy.

Developmental expression of NMDA and AMPA receptor subunits in vestibular nuclear neurons that encode gravity-related horizontal orientations.

We examined the expression profile of subunits of ionotropic glutamate receptors [N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazole-proprionate (AMPA)] during postnatal development of connectivity in the rat vestibular nucleus. Vestibular nuclear neurons were functionally activated by constant velocity off-vertical axis rotation, a strategy to stimulate otolith organs in the inner ear. These neurons indicated Fos expression as a result.

Corticofugal modulation of acoustically induced Fos expression in the rat auditory pathway.

To investigate the corticofugal modulation of acoustic information ascending through the auditory pathway of the rat, immunohistochemical techniques were used to study the functional expression of Fos protein in neurons. With auditory stimulation at different frequencies, Fos expression in the medial geniculate body (MGB), inferior colliculus (IC), superior olivary complex, and cochlear nucleus was examined, and the extent of Fos expression on the two sides was compared. Strikingly, we found densely Fos-labeled neurons in all divisions of the MGB after both presentation of an auditory stimulus and administration of a gamma-aminobutyric acid type A (GABA(A)) antagonist (bicuculline methobromide; BIM) to the auditory cortex.

Maturation of otolith-related brainstem neurons in the detection of vertical linear acceleration in rats.

To investigate the critical maturation time of otolith-related neurons in processing vertical orientations, rats (postnatal day 4 to adults) were studied for functional activation of c-fos expression in brainstem neurons by immuno-/hybridization histochemistry. Conscious rats were subjected to sinusoidal linear acceleration along the vertical plane. Labyrinthectomized and/or stationary controls showed only sporadically scattered Fos-labeled neurons in the vestibular nuclei, confirming an otolithic origin of c-fos expression.

Spatial coding capacity of central otolith neurons.

This review focuses on recent approaches to unravel the capacity of otolith-related brainstem neurons for coding head orientations. In the first section, the spatiotemporal features of central vestibular neurons in response to natural otolithic stimulation are reviewed. Experiments that reveal convergent inputs from bilateral vestibular end organs bear important implications on the processing of spatiotemporal signals and integration of head orientational signals within central otolith neurons.

Fos expression in otolith-related brainstem neurons of postnatal rats following off-vertical axis rotation.

To determine the critical time of responsiveness of developing otolith organ-related brainstem neurons and their distribution, Fos protein expression in response to off-vertical axis rotations (OVAR) was mapped in conscious Sprague Dawley rats from P5 to adulthood. OVAR was used to activate sequentially all utricular hair cells per 360 degrees revolution. We detected the coding of horizontal head positions in otolith organ-related neurons within the vestibular nucleus as early as P7.

Quantitative study of the coexpression of Fos and N-methyl-D aspartate (NMDA) receptor subunits in otolith-related vestibular nuclear neurons of rats.

The expression of NMDA receptor subunits (NR1 and NR2A/B) was demonstrated immunocytochemically in otolith-related neurons within the vestibular nuclear complex and its subnuclei of conscious Sprague-Dawley adult rats. All experimental animals were subjected to constant velocity off-vertical axis rotation (OVAR). The rotating gravity vector during OVAR sequentially activates hair cells on all sectors of the utricular maculae; neurons so activated within the vestibular nuclei were denoted by the expression of Fos protein.