Expanding quasiperiodicity in soft matter: Supramolecular decagonal quasicrystals by binary giant molecule blends.

The quasiperiodic structures in metal alloys have been known to depend on the existence of icosahedral order in the melt. Among different phases observed in intermetallics, decagonal quasicrystal (DQC) structures have been identified in many glass-forming alloys yet remain inaccessible in bulk-state condensed soft matters. Via annealing the mixture of two giant molecules, the binary system assemblies into an axial DQC superlattice, which is identified comprehensively with meso-atomic accuracy. Analysis indicates that the DQC superlattice is composed of mesoatoms with an unusually broad volume distribution. The interplays of submesoatomic (molecular) and mesoatomic (supramolecular) local packings are found to play a crucial role in not only the formation of the metastable DQC superlattice but also its transition to dodecagonal quasicrystal and Frank-Kasper σ superlattices.

Unimolecular Nanoparticles toward More Precise Regulations of Self-Assembled Superlattices in Soft Matter.

The hierarchical self-assembly process opens up great potential for the construction of nanostructural superlattices. Precise regulation of self-assembled superlattices, however, remains a challenge. Even when the primary molecules are precise, the supramolecular motifs (or secondary building blocks) can vary dramatically. In the present work, we propose the concept of unimolecular nanoparticles (UMNPs). The UMNPs act as the supramolecular motif and directly pack into the superlattices. A highly branched giant molecule is presented. We systematically explore its conformations and the superlattice of this giant molecule. Moreover, intriguing complex phases are discovered when blending this UMNP with other conventional giant molecules. These binary mixtures provide direct evidence to support our previously proposed self-sorting process in the self-assembly of "soft alloys". The concept of UMNPs offers a unique approach toward more precise regulation of self-assembled superlattices in soft matter.

Effects of different concentrations of metformin on osteoclast differentiation and apoptosis and its mechanism.

This study aimed to investigate the effect of metformin on osteoclast differentiation and apoptosis. Low concentration of metformin inhibited osteoclast differentiation and downregulated the expression of TRAP, RANK, Cathepsink, NFATC-1, MMP-9 and TRAF-6. High concentration of metformin promoted osteoclast apoptosis and upregulated the expression of Bax/Bcl-2 and caspase-3; BV/TV, BS/TV, Tb.N and BMD were increased while Tp.Sp decreased in the group of intraperitoneal metformin+femoral intramedullary osteoclast injection (Met+OC) compared with the control group, 1 nM metformin downregulated Akt, p44/42 MAPK, JNK, p38 MAPK phosphorylation, 5 nM metformin down regulated ERK and Akt phosphorylation. These results suggest that a low concentration of metformin inhibits osteoclast differentiation through PI3K/Akt and MAPK/ERK signaling pathway; high concentrations of metformin promote osteoclast apoptosis through PI3K/Akt and ERK signaling pathway.

Expressions of IL-12 and its receptors in patients with lumbar disc herniation and their relationship with clinical efficacy.

This study aimed to explore the expressions of interleukin-12 (IL-12) and its receptors IL-23R and IL12RB2 in patients with lumbar disc herniation (LDH) before and after treatment and their relationship with clinical efficacy. A total of 172 LDH patients undergoing surgical treatment in Wuhan Third Hospital, Tongren Hospital of Wuhan University were enrolled as the study group, and 170 healthy subjects as the control group. 5 mL of fasting venous blood was taken before surgery (T0), 1 d (T1), 3 d (T2), 5 d (T3) and 7 d (T4) after treatment respectively. The concentrations of IL-12, IL-23R and IL12RB2 in the two groups were detected, and the correlation between them and the treatment duration and clinical efficacy was analyzed. The study group showed significantly higher serum IL-12, IL-23R and IL12RB2 than the control group before treatment (P < 0.001). In the study group, IL-12, IL-23R and IL-12RB2 were the lowest at T4 (P < 0.001), followed by T3 (P < 0.001). There was no significant difference in IL-23R at T1 and T0 (P > 0.050), and in IL12RB2 at T1 and T2 (P > 0.050). Spearman rank correlation showed that IL-12, IL-23R, IL12RB2 were negatively correlated with treatment duration in the study group (P < 0.001), and were positively correlated with clinical efficacy (P < 0.001). In conclusion, the concentrations of serum IL-12, IL-23R and IL12RB2 in LDH patients are significantly higher than those in normal controls. Moreover, the concentrations are closely related to the rehabilitation of patients and are expected to become therapeutic targets for LDH.

Visible light photoelectrochemical aptasensor for chloramphenicol by using a TiO2 nanorod array sensitized with Eu(III)-doped CdS quantum dots.

A visible-light driven photoelectrochemical (PEC) aptasensor is described that is capable of detecting chloramphenicol (CAP). It is based on the use of a TiO2 based nanorod array (NRA) sensitized with Eu(III)-doped CdS quantum dots. The NRA absorbs visible-light and while strongly depressing the recombination of photogenerated charges, thereby improving photo-to-current conversion efficiency. The introduction of Eu(III) ions promotes the charge transformation and utilization, and this results in a further increase of photocurrent. The NRA was employed as the photoactive material for the fabrication of a PEC aptasensor. CAP-binding aptamers were immobilized on a fluorine-doped tin oxide (FTO) electrode that was modified with the NRA. The aptasensor was applied to the determination of CAP by monitoring the decrease in photocurrent (at a typical voltage of 0 V) that is caused by the formation of the aptamer-CAP complex. Under optimal conditions, the response is linear in the 1.0 pM to 3.0 nM CAP concentration range, with a detection limit of 0.36 pM (at S/N = 3). The method was applied to the determination of CAP in spiked milk samples where it gave satisfactory results. Graphical abstract Schematic presentation of the fabrication of a visible-light driven photoelectrochemical aptasensor based on the use of a TiO2 nanorod array sensitized with Eu(III)-doped CdS quantum dots. It was applied to the determination of chloramphenicol with good selectivity and high sensitivity. TiO2 NRA: TiO2 nanorod array; FTO: fluorine-doped tin oxide; CdS:Eu3+ QDs: Eu(III)-doped CdS quantum dots; BSA: bovine serum albumin; CAP: chloramphenicol.

Oxidative stress induction by narasin augments doxorubicin's efficacy in osteosarcoma.

Complications and fata toxicity induced by chemotherapy are the main challenge for clinical management of osteosarcoma. The identification of agents that can augment the efficacy of chemotherapy at lower doses may represent an alternative therapeutic strategy. Narasin is a polyether antibiotic widely used in veterinary medicine. In this study, we show that narasin is active against osteosarcoma cells at the same concentrations that are less toxic to normal cells. This effect is achieved by growth inhibition and apoptosis induction, which is mediated by oxidative stress and damage, and mitochondrial dysfunction. The antioxidant N-acetyl-l-cysteine (NAC) abolishes the anti-osteosarcoma activity. Importantly, narasin significantly augments doxorubicin's efficacy in both osteosarcoma cell culturing system and subcutaneous implantation mouse model. The combination of narasin and doxorubicin at non-toxic doses completely arrests osteosarcoma growth in mice. Our results suggest that the concurrent administration of doxorubicin and narasin could present a viable alternative therapeutic approach for osteosarcoma.

Discovery of a series of 2-(1H-pyrazol-1-yl)pyridines as ALK5 inhibitors with potential utility in the prevention of dermal scarring.

A series of 2-(1H-pyrazol-1-yl)pyridines are described as inhibitors of ALK5 (TGFß receptor I kinase). Modeling compounds in the ALK5 kinase domain enabled some optimization of potency via substitutions on the pyrazole core. One of these compounds PF-03671148 gave a dose dependent reduction in TGFß induced fibrotic gene expression in human fibroblasts. A similar reduction in fibrotic gene expression was observed when PF-03671148 was applied topically in a rat wound repair model. Thus these compounds have potential utility for the prevention of dermal scarring.

[Drugs and the mechanism for reversing the tolerance of flurazepan in rats].

OBJECTIVE: Benzodiazepines (BDZ) have many effects on various kinds of epilepsies, but long-term treatment with BDZ often leads to drug tolerance. This study aimed to seek drugs which can reverse the tolerance of flurazepam (FZP), and to explore the role of neuropeptide Y (NPY) in the reversal effect. METHODS: A rat model of anticonvulsant tolerance to FZP was prepared. The rats with FZP tolerance were randomly assigned to seven groups: FZP-tolerance, and nifedipine, levetiracetam, topiramate, flumazenil, L-NAME and pyridoxamine treatment groups. The tolerance to FZP was evaluated through pentylenetetrazol (PTZ) infusion into a tail vein. The latency to onset of clonic seizure and the PTZ threshold were recorded. The mRNA of NPY receptor Y2 in the hippocampus was determined by RT-PCR, and the distribution of NPY in the hippocampus was examined by immunohistochemistry. RESULTS: In comparison with the blank control group, the average latency to the onset of clonic seizure was shortened, the average PTZ threshold decreased and the expression of NYT and NPY receptor Y2 mRNA decreased significantly in the FZP-tolerance group (p<0.01). In comparison with the FZP-tolerance group, the average latency to onset of clonic seizure was prolonged by 2 times and the average PTZ threshold doubled in the topiramate treatment group. The average latency to onset of clonic seizure was prolonged by 1 time and the average PTZ threshold increased 1 time in the nifedipine, the levetiracetam and the flumazenil treatment groups. The mRNA expression of NPY receptor Y2 increased by 1 or 2 times in the flumazenil, the nifedipine and the topiramate treatment groups when compared with the FZP-tolerance group. CONCLUSIONS: Nifedipine, levetiracetam, topiramate and flumazenil can reverse the anticonvulsant tolerance to flurazepam. NPY may play a role in mediating the reversal effect.

Preparation and Properties of Hydrophilic Rosin-Based Aromatic Polyurethane Microspheres.

Hydrophilic aromatic polyurethane (HAPU) microspheres were prepared through dispersion polymerization of a rosin-based polyurethane dispersion with C=C and styrene (St). The effects of the monomer ratio (i.e., waterborne rosin-based aromatic polyurethane (WRPU) to St), dispersant level, and reaction temperature on the properties of the microspheres were investigated; the effects of pH and adsorption temperature on the adsorption capacity of Orange II were also studied. The microspheres were characterized using Fourier transform infrared spectroscopy, energy-dispersive spectrometry, thermogravimetric analysis, laser particle size analysis, and scanning electron microscopy. The results showed that HAPU microspheres have been successfully synthesized and the produced microspheres exhibited good thermal stability and monodispersion. The optimum reaction conditions for the preparation of the microspheres were determined as a monomer ratio (m WRPU/m St) of 6:4 with 8 wt % poly(vinyl pyrrolidine) (on the basis of the mixed monomer) at 80 °C for 8 h. Under these conditions, the average particle size of the synthetic microspheres was 120 nm and the particle size distribution index was 0.442. The microspheres' adsorption capacity for Orange II reached 17.53 mg·g-1 when the solid-liquid ratio was 1 g·L-1, with an initial concentration of 100 mg·L-1 at pH 5, and the adsorption was conducted at 313 K for 3 h.

3'UTR-dependent localization of a Purkinje cell messenger RNA in dendrites.

Pcp2(L7) is a Purkinje cell-specific GoLoco domain protein that modulates activation of Galphai/o proteins by G protein-coupled receptors. A likely downstream effector of this pathway is the P-type Ca(2+) channel, and thereby, the intrinsic electrophysiology of Purkinje cells could be modulated by Pcp2(L7). It has long been known that the Pcp2(L7) mRNA is abundantly localized in dendrites, suggesting the possibility of distal synthesis and local changes in levels of the protein. As a first step to uncover the trafficking and translational mechanisms for this mRNA, we have begun identifying the cis-acting sequences important for its localization in dendrites. Using expression of modified transgenes in vivo, we show that the 3'UTR, only 65 bases long, is necessary in this process.

Melatonin promotes ripening of grape berry via increasing the levels of ABA, H2O2, and particularly ethylene.

The role of melatonin in the regulation of fruit ripening and the mechanism involved remain largely unknown. In "Moldova" grape berries, melatonin accumulated rapidly from onset of veraison, reached the maximum at 94 days after bloom (DAB) and then exhibited low levels at late stages of berry ripening. By contrast, abscisic acid (ABA) and hydrogen peroxide (H2O2) exhibited different accumulation patterns, and ethylene was primarily produced immediately before veraison. Further experiments demonstrated that 10 and particularly 100 µM melatonin treatments increased the levels of ABA, H2O2, and ethylene production and promoted berry ripening compared with the control treatment, whereas 0.1 and 1.0 µM melatonin did not lead to clear effects. Additionally, the application of inhibitors indicated that ABA, H2O2, and ethylene participated in the regulation of berry ripening induced by melatonin, and the suppression of ethylene biosynthesis produced the greatest inhibitory effects on melatonin-induced berry ripening compared with those of ABA and H2O2. Melatonin also promoted ethylene production via ABA. In summary, 10 and particularly 100 µM melatonin treatments promoted berry ripening, which was accomplished, at least partially, via the other signaling molecules of ABA, H2O2, and particularly ethylene. This research provides insight into melatonin signaling during berry ripening and may advance the application of melatonin to accelerate berry ripening.

Influence of vitamin D deficiency on T cell subsets and related indices during spinal tuberculosis.

The present study investigated the effects of vitamin D deficiency on T cell subsets in patients with spinal tuberculosis. In addition, the influence of vitamin D deficiency was investigated on the expression of cytokines IL-1ß, IL-6 and TNF-α in intervertebral disc lesions of patients. One hundred and seventeen patients with spinal tuberculosis who received operative treatment in the Department of Orthopedics in Wuhan City Third Hospital from March 2012 to March 2015 were collected. The patients were divided depending upon vitamin D content into the control group (64 cases, vitamin D content <25 nmol/l) and experimental group (53 cases, vitamin D content >50 nmol/l). Immunofluorescence method was applied to determine the content of T cell subsets in both groups of patients. Intervertebral disc lesion tissues of two groups of patients were obtained during surgery then treated with HE staining and immunohistochemical staining. The values of average optical density obtained under light microscope were observed as the expression quantities of IL-1ß, IL-6 and TNF-α, to explore the relationship between vitamin D and the expression of cytokines. When vitamin D is lacking, the expression of T lymphocyte subsets in patients with spinal tuberculosis significantly decreased. Compared with experimental group, the difference was statistically significant (P<0.05). Further, the expression of cytokines IL-1ß, IL-6 and TNF-α in intervertebral disc lesion tissues of patients with spinal tuberculosis were significantly higher than those of patients with spinal tuberculosis whose vitamin D content was normal (P<0.05). In the control group, vitamin D content was negatively correlated with the expression of IL-1ß, IL-6 and TNF-α. The expression of T lymphocyte subsets in patients with vitamin D deficiency was significantly reduced, and the immune function decreased. The expression of IL-1ß, IL-6 and TNF-α in lesions were significantly higher than those of patients with normal vitamin D content. In addition, the lower the content of vitamin D was, the more active the expression of inflammatory factors were, which was not conducive to the recovery of tuberculosis lesions.

Melatonin Enhances Phenolics Accumulation Partially via Ethylene Signaling and Resulted in High Antioxidant Capacity in Grape Berries.

This study assessed the primary impacts of exogenous melatonin (MT) treatment on grape berry metabolism. Exogenous MT treatment increased the endogenous MT content and modified berry ripening. Transcriptomic analysis revealed that the processes of polyphenol metabolism, carbohydrate metabolism and ethylene biosynthesis and signaling were the three most significantly altered biological processes upon MT treatment. Further experiments verified that MT treatment increased the contents of total anthocyanins, phenols, flavonoids and proanthocyanidins in berries. Additionally, the contents of 18 of the 22 detected individual phenolic compounds were enhanced by MT treatment; particularly, the resveratrol content was largely increased concomitantly with the up-regulation of STS gene expression. Meanwhile, MT treatment enhanced the antioxidant capacity of berries. On the other hand, it was indicated that ethylene participated in the regulation of polyphenol metabolism and antioxidant capacity under MT treatment in grape berries. In summary, MT enhances the polyphenol content and antioxidant capacity of grape berries partially via ethylene signaling.

Efficacy of topical administration of Radix Euphorbiae Ebracteolatae on multiple plantar warts: A parallel randomized trial.

OBJECTIVE: To investigate the clinical efficacy of Radix Euphorbiae Ebracteolatae in treating multiple plantar warts. METHODS: Twenty-eight patients with multiple plantar warts on both left and right feet were recruited. Warts on the left feet (treatment group) of all patients were externally treated with moderate ethanol extract of Radix Euphorbiae Ebracteolatae which was made of 30 g Radix Euphorbiae Ebracteolatae putting into 100 mL of medical ethanol (75%). For the control group, moderate dose of 0.1% vitamin A acid ointment was externally applied onto the right-foot warts. The topical application of each treatment was conducted 3 times a day for both groups. After 4 and 8 weeks, the efficacy and side effects including skin erythema and blister were evaluated and observed. RESULTS: Compared with the pre-treatment, warts size of the control group was reduced after 8-week treatment (P<0.05). After 4 and 8 weeks, the average wart size in the treatment group was both significantly reduced respectively (P<0.01). There were significant differences in warts size and total effective rate between the two groups after 4-week treatment respectively (P<0.05 or P<0.01). More significant differences in wart size and total effective rate were observed after 8-week treatment (P<0.05 or P<0.01). The percentage reduction in wart size was significantly different between the two groups after 4 and 8-week treatment (P<0.01). CONCLUSION: Radix Euphorbiae Ebracteolatae was significantly superior to vitamin A acid ointment in treating multiple plantar warts.

Calcium channel alpha2-delta type 1 subunit is the major binding protein for pregabalin in neocortex, hippocampus, amygdala, and spinal cord: an ex vivo autoradiographic study in alpha2-delta type 1 genetically modified mice.

Pregabalin is a synthetic amino acid compound effective in clinical trials for the treatment of post-herpetic neuralgia, diabetic peripheral neuropathy, generalized anxiety disorder and adjunctive therapy for partial seizures of epilepsy. However, the mechanisms by which pregabalin exerts its therapeutic effects are not yet completely understood. In vitro studies have shown that pregabalin binds with high affinity to the alpha(2)-delta (alpha(2)-delta) subunits (Type 1 and 2) of voltage-gated calcium channels. To assess whether alpha(2)-delta Type 1 is the major central nervous system (CNS) binding protein for pregabalin in vivo, a mutant mouse with an arginine-to-alanine mutation at amino acid 217 of the alpha(2)-delta Type 1 protein (R217A mutation) was generated. Previous site-directed mutagenesis studies revealed that the R217A mutation dramatically reduces alpha(2)-delta 1 binding to pregabalin in vitro. In this autoradiographic analysis of R217A mice, we show that the mutation to alpha(2)-delta Type 1 substantially reduces specific pregabalin binding in CNS regions that are known to preferentially express the alpha(2)-delta Type 1 protein, notably the neocortex, hippocampus, basolateral amygdala and spinal cord. In mutant mice, pregabalin binding was robust throughout regions where the alpha(2)-delta Type 2 subunit mRNA is abundant, such as cerebellum. These findings, in conjunction with prior in vitro binding data, provide evidence that the alpha(2)-delta Type 1 subunit of voltage-gated calcium channels is the major binding protein for pregabalin in CNS. Moreover, the distinct localization of alpha(2)-delta Type 1 and mutation-resistant binding (assumed to be alpha(2)-delta Type 2) in brain areas subserving different functions suggests that identification of subunit-specific ligands could further enhance pharmacologic specificity.

Axonopathy, tau abnormalities, and dyskinesia, but no neurofibrillary tangles in p25-transgenic mice.

Neurofibrillary tangles, one of the pathologic hallmarks of Alzheimer's disease (AD), are composed of abnormally polymerized tau protein. The hyperphosphorylation of tau alters its normal cellular function and is thought to promote the formation of neurofibrillary tangles. Growing evidence suggests that cyclin-dependent kinase 5 (cdk5) plays a role in tau phosphorylation, but the function of the enzyme in tangle formation remains uncertain. In AD, cdk5 is constitutively activated by p25, a highly stable, 25kD protein thought to be increased in the AD brain. To test the hypothesis that p25/cdk5 interactions promote neurofibrillary pathology, we created transgenic mouse lines that overexpress the human p25 protein specifically in neurons. Mice with high transgenic p25 expression have augmented cdk5 activity and develop severe hindlimb semiparalysis and mild forelimb dyskinesia beginning at approximately 3 months of age. Immunohistochemical and ultrastructural analyses showed widespread axonal degeneration with focal accumulation of tau in various regions of the brain and, to a lesser extent, the spinal cord. However, there was no evidence of neurofibrillary tangles in neuronal somata or axons, nor were paired helical filaments evident ultrastructurally. These studies confirm that p25 overexpression can lead to tau abnormalities and axonal degeneration in vivo but do not support the hypothesis that p25-related induction of cdk5 is a primary event in the genesis of neurofibrillary tangles.

Exogenous induction of cerebral beta-amyloidosis in betaAPP-transgenic mice.

A key commonality of most age-related neurodegenerative diseases is the accumulation of aggregation-prone proteins in the brain. Except for the prionoses, the initiation and propagation of these proteopathies in vivo remains poorly understood. In a previous study, we found that the deposition of the amyloidogenic peptide Abeta can be induced by injection of dilute extracts of Alzheimeric neocortex into the brains of Tg2576 transgenic mice overexpressing the human beta-amyloid precursor protein. The present study was undertaken to assess the pathology after long-term (12 months) incubation, and to clarify the distinctive anatomical distribution of seeded Abeta-immunoreactivity. All mice were injected at 3 months of age; 5 months later, as expected, Abeta deposits were concentrated mostly in the injected hemisphere. After 12 months, abundant, transgene-derived Abeta deposits were present bilaterally in the forebrain, but plaque load was still clearly greater in the extract-injected hemisphere. There was also evidence of tau hyperphosphorylation in axons of the corpus callosum that had been injured by the injection, most prominently in transgenic mice, but also, to a lesser degree, in non-transgenic mice. Five months following injection of AD-extract, an isolated cluster of Abeta-immunoreactive microglia was sometimes evident in the ipsilateral entorhinal cortex; the strong innervation of the hippocampus by entorhinal cortical neurons suggests the possible spread of seeded pathology from the injection site via neuronal transport mechanisms. Finally, using India Ink to map the local dispersion of injectate, we found that Abeta induction is especially potent in places where the injectate is sequestered. The AD-seeding model can illuminate the emergence and spread of cerebral beta-amyloidosis and tau hyperphosphorylation, and thus could enhance our understanding of AD and its pathogenic commonalties with other cerebral proteopathies.

Gap junction -mediated cAMP movement between oocytes and somatic cells.

Cyclic AMP (cAMP) plays a critical role in oocyte meiotic maturation. However, the source of cAMP surge prior to maturation and the direction of gap junction-dependent cAMP movement are unclear. In this study, inhibition of gap junctional communication (GJC) using carbenoxolone (3.5 h) induced meiotic resumption in ~90% of follicle-enclosed oocytes (FEOs). The concentration of cAMP in a single oocyte was higher than that in a single cumulus cell, suggesting that the movement of cAMP proceeds from the oocyte to cumulus cells under passive diffusion. The mRNAs of adenylyl cyclases and the corresponding proteins were mainly detected in oocytes. Persistent or transient incubation with forskolin induced meiotic resumption in FEOs. The maturation induced by persistent forskolin treatment was inhibited by carbenoxolone. However, carbenoxolone had no effect on the maturation of FEOs transiently treated with forskolin or persistently treated with follicle-stimulating hormone. Oocyte maturation was inhibited by sequential treatment with carbenoxolone followed by forskolin. The carbenoxolone-induced maturation was accompanied by a cAMP surge, increased PDE3A and MAPK activation, and decreased levels of cGMP and cAMP-dependent PKA I activation.

Pregabalin is a potent and selective ligand for α(2)δ-1 and α(2)δ-2 calcium channel subunits.

Pregabalin, a synthetic branched chain γ-amino acid with anticonvulsant, anxiolytic, and analgesic activities, has been shown to bind with high affinity to the voltage-gated calcium channel α(2)δ subunit. Given the broad therapeutic utility of pregabalin, a series of experiments was undertaken to determine the potency, selectivity, and specificity of pregabalin's receptor-binding profile at α(2)δ-1 and α(2)δ-2 subunits of voltage-gated calcium channels along with 38 widely studied receptors and channels. Receptor autoradiography was used to assess regional-binding density of pregabalin throughout the rat spinal cord and brain. In addition, a series of studies using in vivo electrophysiological recordings of γ-aminobutyric acid (GABA)(A)- and GABA(B)-evoked currents was undertaken to determine the interaction of pregabalin with GABAergic receptor subtypes. Together, the results of these studies demonstrate potent and selective binding of pregabalin to α(2)δ-1 and α(2)δ-2 subunits in native and recombinant human and porcine systems. Pregabalin did not interact with any of the 38 receptors and ion channels evaluated, and a variety of central nervous system (CNS)-targeted therapeutic drugs did not show activity at the α(2)δ subunits of voltage-gated calcium channels. Receptor autoradiography demonstrated extensive [(3)H]-pregabalin binding throughout the CNS, with high-level binding in the cortex, hippocampus, cerebellum, dorsal horn of the spinal cord, and amygdala. Finally, receptor-binding and electrophysiological techniques failed to show evidence of an interaction between pregabalin and GABA(A) or GABA(B) receptors. These studies suggest that the clinical effects of pregabalin are likely due to direct and selective interactions with α(2)δ-1 and α(2)δ-2 subunits of voltage-gated calcium channels.

An activin receptor-like kinase 5 inhibitor reduces collagen deposition in a rat dermal incision wound healing model.

BACKGROUND: Excessive dermal scarring is characterized by an overabundant deposition of extracellular matrix caused by fibrosis. The purpose of this study was to modify a rodent model of cutaneous healing for use in the development of compounds to minimize scarring, and to test the model with a small molecule inhibitor of transforming growth factor-ß type I receptor, activin receptor-like kinase 5, because this class of inhibitors has been demonstrated to be effective in minimizing fibrosis in other organs. METHODS: The rodent model of cutaneous healing consists of uniform full-thickness incisional dermal wounds in rats. Wounds were allowed to heal by secondary intention, generally over a 14-day period. The usefulness of the model was tested by the application of an activin receptor-like kinase 5 inhibitor, CP-639180. Activin receptor-like kinase 5 inhibition antagonizes the transforming growth factor-ß pathway, and was used to determine whether there was an effect on collagen deposition in wounds. The compound was applied once per day for 7 days starting at postwounding day 0 or 7 (early or late treatment regimens). Wounds were analyzed histologically for collagen deposition and biochemically for quantification of collagen changes. RESULTS: Early and late treatment regimens with the activin receptor-like kinase 5 inhibitor significantly reduced collagen deposition without impairing wound healing. CONCLUSIONS: Application of a small molecular inhibitor of activin receptor-like kinase 5 appears to significantly reduce collagen deposition in rat dermal wounds as reported here for the first time. Activin receptor-like kinase 5 inhibition may offer a novel approach to reducing proliferative scars in humans because collagen accumulation is a core event in scarring.