Search

In our in vitro studies, one dual stapled peptide out of the series of candidates (TP4-3: FIIXKKSXGLFKKKAGAXKKKXIKK ) showed significant activity, low toxicity, and high stability (in 50% human serum). When tested in cecal ligation and puncture (CLP) mouse models of polymicrobial sepsis, TP4-3 improved survival (87.5% on day 7).

Author(s): Chang, Huiyi H; Yeh, Jih-Chao; Mao, Jackie; Ginsberg, David A; Ghoniem, Gamal; Rodriguez, Larissa V | Abstract: AimInterstitial cystitis/painful bladder syndrome/(IC/PBS) results in recurring pain in the bladder and surrounding pelvic region caused by abnormal excitability of micturition reflexes. Spinal cord stimulation (SCS) is currently clinically used for the attenuation of neuropathic and visceral pain. The present study examined whether SCS at upper lumbar segments modulates detrusor overactivity and visceral hyperalgesia associated with cystitis in a rat model of cyclophosphamide (CYP)-induced cystitis.MethodsCystitis was induced by intraperitoneal injection of CYP (200 mg/kg) in six adult female Sprague Dawley rats 48 h prior to urodynamic recordings. Another six rats served as-controls with saline injection. Cystometry and the external urethral sphincter (EUS) electromyography during bladder infusion were evaluated under urethane anesthesia. The visceromotor reflexes (VMR) obtained from the external abdominal oblique muscle were quantified during bladder infusion and isotonic bladder distension (IBD), respectively. After baseline recordings were taken, SCS was applied on the dorsal surface of L3 for 25 min. Urodynamic recordings and VMR during bladder infusion and IBD were repeated 2 h after SCS.ResultsCYP resulted in detrusor overactivity, stronger EUS tonic contractions, and increased VMR. SCS significantly reduced non-voiding contractions, prolonged EUS relaxation, and delayed VMR appearance during bladder infusion as well as significantly decreased VMR during IBD in cystitis rats.ConclusionSCS improved bladder function and EUS relaxation during bladder infusion and significantly attenuated visceral nociceptive-related VMR during IBD in cystitis rats. SCS may have therapeutic potential for patients with hyperalgesia and IC/PBS.

INTRODUCTION AND OBJECTIVE:Rats exposed to water avoidance stress (WAS) show increased urinary frequency, increased somatosensory nociceptive reflex responses, as well as altered brain responses to...

OBJECTIVE: The underlying mechanism of interstitial cystitis/bladder pain syndrome (IC/BPS) is not well understood and evaluation of current therapeutic interventions have not identified any generally effective treatments. Physical activity has shown beneficial effects on individuals suffering from chronic pain. Anxiety-prone rats exposed to water avoidance stress (WAS) develop urinary frequency and lower bladder sensory thresholds with high face and construct validity for the study of IC/BPS. The aim of this study was to evaluate the role of chronic voluntary exercise on urinary frequency, voiding function, and hyperalgesia in animals exposed to WAS. MATERIALS AND METHODS: Twenty-six female Wistar-Kyoto rats were exposed to WAS and thereafter randomized to either voluntary exercise for 3 weeks or sedentary groups. Voiding parameters were assessed at baseline, post-WAS, and weekly for 3 weeks. Prior to euthanasia, the animals underwent cystometrogram (CMG), external urinary sphincter electromyography (EUS EMG), and assessment of visceromotor response (VMR) to isotonic bladder distension (IBD). RESULTS: WAS exposure resulted in adverse changes in voiding parameters. Compared to sedentary animals, animals in the voluntary exercise group had improved voiding parameters during metabolic cage and CMG testing, as well as improved bladder sensory thresholds as determined by VMR during IBD. CONCLUSION: Voluntary exercise in an animal model of chronic stress leads to improvement in voiding function and visceral bladder hyperalgesia.

Copolymeric micelles made from dextran-g-lauric acid were optimized to carry IκB kinase-β inhibitor, IMD-0354, to form a drug delivery system and to verify the effects on drug loading and encapsulation efficiency. Dextran with different molecular weights was modified by lauric acid via an esterification process between the hydroxyl group of dextran and the carboxyl group of lauric acid. The hydrophilic dextran acts as a framework and lauric acid was grafted to its branches, forming an amphiphilic polymer. Fourier transform infrared spectrometry and 1H nuclear magnetic resonance (NMR) were used to confirm and calculate the grafting percentage of dextran-g-lauric acid. The critical micelle concentration (CMC) values were obtained using ultraviolet-visible spectrophotometry, and particle size was measured using dynamic light scattering and transmission electron microscopy (TEM). The effect of drug-loaded micelles was verified using cell viability and immunofluorescence staining. TEM images indicated that the self-assembled micelles are spherical in shape. The drug loading percentage of micelles was 0.76–4.67%, and the encapsulation efficiency was 15.4–93.75%. Regulating the hydrophilic and hydrophobic fragments of dextran-g-lauric acid changed the particle size, grafting rate, CMC, drug loading, and encapsulation efficiency of the polymer. IMD-0354-loaded micelles showed higher apoptosis expression in melanoma than free IMD-0354. This shows that controlled interactions of hydrophilic and hydrophobic regions on dextran-g-lauric acid may have profound effects on drug delivery for cancer treatment.

Osteoporosis is a result of imbalance between bone formation by osteoblasts and resorption by osteoclasts (OCs). In the present study, we investigated the potential of limiting the aggravation of osteoporosis by reducing the activity of OCs through thermolysis. The proposed method is to synthesize bisphosphonate (Bis)-conjugated iron (II, III) oxide (Fe3O4) nanoparticles and incorporate them into OCs. The cells should be subsequently exposed to radiofrequency (RF) to induce thermolysis. In this study, particles of Fe3O4 were first synthesized by chemical co-precipitation and then coated with dextran (Dex). The Dex/Fe3O4 particles were then conjugated with Bis to form Bis/Dex/Fe3O4. Transmission electron microscopy revealed that the average diameter of the Bis/Dex/Fe3O4 particles was ~20 nm. All three kinds of nanoparticles were found to have cubic inverse spinel structure of Fe3O4 by the X-ray diffraction analysis. Fourier transform infrared spectroscopy confirmed that the Dex/Fe3O4 and Bis/Dex/Fe3O4 nanoparticles possessed their respective Dex and Bis functional groups, while a superconducting quantum interference device magnetometer measured the magnetic moment to be 24.5 emu. In addition, the Bis/Dex/Fe3O4 nanoparticles were fully dispersed in double-distilled water. Osteoblasts and OCs were individually cultured with the nanoparticles, and an MTT assay revealed that they were non-cytotoxic. An RF system (42 kHz and 450 A) was used to raise the temperature of the nanoparticles for 20 minutes, and the thermal effect was found to be sufficient to destroy OCs. Furthermore, in vivo studies verified that nanoparticles were indeed magnetic resonance imaging contrast agents and that they accumulated after being injected into the body of rats. In conclusion, we developed a water-dispersible magnetic nanoparticle that had RF-induced thermogenic properties, and the results indicated that the Bis/Dex/Fe3O4 nanoparticle had the potential for controlling osteoporosis.

The brain-derived neurotrophic factor (BDNF) is vital in the neural differentiation of neural stem/progenitor cells, and together may have therapeutic potential for neural regeneration. In this study, a multiplexed polybutylcyanoacrylate nanoparticle (PBCA NP) delivery platform was constructed, incorporating either surface-adsorbed or encapsulated BDNF for the induction of neural differentiation in induced pleuripotent stem cells (iPSCs), where tween 80 (T80) and superparamagnetic iron oxide (SPIO) were added for central nervous system (CNS) targeting and magnetic resonance (MR) image tracking, respectively. Both methods by which the BDNF was carried resulted in loading efficiencies greater than 95%. The nanoparticle-mediated delivery of BDNF resulted in neural differentiation of iPSCs detected on immunofluorescence staining as early as 7 days, with enhanced differentiation efficiency by 1.3-fold compared to the control on flow cytometry, the delivery system of surface-adsorbed BDNF gave rise to cells that had the best neural development than the encapsulated formulation. T80-coating disrupted the in vitro blood&ndash, brain barrier model with a corresponding 1.5- to two-fold increase in permeability. SPIO-loaded PBCA NPs exhibited a concentration-dependent, rapid decay in signal intensity on the phantom MR experiment. This study demonstrates the versatility of the PBCA NP, and the surface-adsorption of BDNF is the preferred method of delivery for the differentiation of iPSCs.

PurposeThis study investigated the effect of gabapentin on lower urinary tract dysfunction focusing on urethral activities and cystitis-induced hyperalgesia in a mouse model of painful bladder syndrome/interstitial cystitis (PBS/IC). The electromyography(EMG) of external urethral sphincter(EUS) was difficult to obtain, but contained useful information to examine the drug effect in mice.MethodsFemale C57BL/6J mice were intraperitoneally (ip) administration with either saline or 200mg/kg of cyclophosphamide (CYP) 48h before experimental evaluation. Cystitis mice were treated with administration of gabapentin (25 or 50mg/kg, ip). Cystometry and EUS EMG were obtained and analyzed during continuous bladder infusion. The visceral pain-related visceromotor reflex (VMR) was recorded in response to isotonic bladder distension.ResultsCystitis mice showed shorter inter-contraction intervals and increased occurrence of non-voiding contractions during bladder infusion, with increased VMR during isotonic bladder distension, indicating cystitis-induced bladder hyperalgesia. Gabapentin (50mg/kg) suppressed effects of CYP on cystometry, but not on EUS EMG activity, during bladder infusion. The effect on urodynamic recordings lasted 4h. VMR was significantly reduced by gabapentin.ConclusionsThe present study showed that CYP-induced cystitis in mice is a model of visceral hyperalgesia affecting detrusor contractions, not urethral activations. The technique of using EUSEMG to evaluate the drug effects on urethral activities is novel and useful for future investigations. Gabapentin can be as a potential treatment for detrusor overactivity and PBS/IC.

Spinal cord epidural stimulation (SCS) represents a form of neuromodulation for the management of spasticity and pain. This technology has recently emerged as a new approach for potentially augmenting locomotion and voiding function in humans and rodents after spinal cord injury. However, the effect of SCS on micturition has not been studied extensively. Here, SCS was first applied as a direct stimulus onto individual segmental levels of the lumbar spinal cord in rats to map evoked external urethral sphincter (EUS) electromyography activity and SCS-induced voiding contractions. SCS of L2-3 inhibited EUS tonic activity, and SCS on L3 (L3/SCS) inhibited EUS tonic activity and elicited EUS bursting. In contrast, SCS of L1 and L4-6 evoked EUS tonic contractions, which resembled the urethral guarding reflex during bladder storage. Next, the effects of a bilateral pelvic nerve crush (PNC) injury on urodynamic function were examined at 14 days post-operatively. The PNC injury resulted in decreased voiding efficiency and maximum intravesical pressure, whereas the post-voiding residual volume was increased, suggestive of an underactive bladder. Finally, L3/SCS was performed to induce a voiding contraction and enable voiding in rats with a PNC injury. Voiding efficiency was significantly increased, and the residual volume was decreased by L3/SCS in rats after the PNC injury. We conclude that L3/SCS may be used to induce micturition reflexes in a partially filled bladder, reduce urethral resistance, and augment bladder emptying after PNC injury.

Background Rats exposed to water avoidance stress (WAS) show increased urinary frequency, increased somatosensory nociceptive reflex responses, as well as altered brain responses to bladder distension, analogous to similar observations made in patients with urologic chronic pelvic pain syndrome (UCPPS). Exercise has been proposed as a potential treatment option for patients with chronic urinary frequency and urgency. We examined the effects of exercise on urinary voiding parameters and functional brain activation during bladder distension in rats exposed to WAS. Methods Adult, female Wistar Kyoto rats were exposed to 10 days of WAS and thereafter randomized to either voluntary exercise for 3 weeks or sedentary groups. Voiding parameters were assessed at baseline, post-WAS, and weekly for 3 weeks. Thereafter, cerebral blood flow (CBF) mapping was performed during isotonic bladder distension (20 cm H2O) after intravenous bolus injection of [14C]-iodoantipyrine. Regional CBF was quantified in autoradiographs of brain slices and analyzed in 3-D reconstructed brains by statistical parametric mapping. Functional connectivity was examined between regions of the micturition circuit through interregional correlation analysis. Results WAS exposure in sedentary animals (WAS/no-EX) increased voiding frequency and decreased urinary volumes per void. Exercise exposure in WAS animals (WAS/EX) resulted in a progressive decline in voiding frequency back to the baseline, as well as increased urinary volumes per void. Within the micturition circuit, WAS/EX compared to WAS/no-EX demonstrated a significantly lower rCBF response to passive bladder distension in Barrington's nucleus that is part of the spinobulbospinal voiding reflex, as well as in the periaqueductal gray (PAG) which modulates this reflex. Greater rCBF was noted in WAS/EX animals broadly across corticolimbic structures, including the cingulate, medial prefrontal cortex (prelimbic, infralimbic areas), insula, amygdala, and hypothalamus, which provide a ‘top-down’ decision point where micturition could be inhibited or triggered. WAS/EX showed a significantly greater positive brain functional connectivities compared to WAS/no-EX animals within regions of the extended reflex loop (PAG, Barrington's nucleus, intermediodorsal thalamic nucleus, pons), as well as within regions of the corticolimbic decision-making loop of the micturition circuit, with a strikingly negative correlation between these pathways. Urinary frequency was positively correlated with rCBF in the pons, and negatively correlated with rCBF in the cingulate cortex. Conclusion Our results suggest that chronic voluntary exercise may decrease urinary frequency at two points of control in the micturition circuit. During the urine storage phase, it may diminish the influence of the reflex micturition circuit itself, and/or it may increase corticolimbic control of voiding. Exercise may be an effective adjunct therapeutic intervention for modifying the urinary symptoms in patients with UCPPS.

This work has developed a novel approach to form common carotid artery (CCA) thrombus in rats with a wireless implantable light-emitting diode (LED) device. The device mainly consists of an external controller and an internal LED assembly. The controller was responsible for wirelessly transmitting electrical power. The internal LED assembly served as an implant to receive the power and irradiate light on CCA. The thrombus formation was identified with animal sonography, 7T magnetic resonance imaging, and histopathologic examination. The present study showed that a LED assembly implanted on the outer surface of CCA could induce acute occlusion with single irradiation with 6 mW/cm2LED for 4 h. If intermittent irradiation with 4.3–4.5 mW/cm2LED for 2 h was shut off for 30 min, then irradiation for another 2 h was applied; the thrombus was observed to grow gradually and was totally occluded at 7 days. Compared with the contralateral CCA without LED irradiation, the arterial endothelium in the LED-irradiated artery was discontinued. Our study has shown that, by adjusting the duration of irradiation and the power intensity of LED, it is possible to produce acute occlusion and progressive thrombosis, which can be used as an animal model for antithrombotic drug development.

Osteoporosis is a result of imbalance between bone formation by osteoblasts and resorption by osteoclasts (OCs). In the present study, we investigated the potential of limiting the aggravation of osteoporosis by reducing the activity of OCs through thermolysis. The proposed method is to synthesize bisphosphonate (Bis)-conjugated iron (II, III) oxide (Fe3O4) nanoparticles and incorporate them into OCs. The cells should be subsequently exposed to radiofrequency (RF) to induce thermolysis. In this study, particles of Fe3O4 were first synthesized by chemical co-precipitation and then coated with dextran (Dex). The Dex/Fe3O4 particles were then conjugated with Bis to form Bis/Dex/Fe3O4. Transmission electron microscopy revealed that the average diameter of the Bis/Dex/Fe3O4 particles was ~20 nm. All three kinds of nanoparticles were found to have cubic inverse spinel structure of Fe3O4 by the X-ray diffraction analysis. Fourier transform infrared spectroscopy confirmed that the Dex/Fe3O4 and Bis/Dex/Fe3O4 nanoparticles possessed their respective Dex and Bis functional groups, while a superconducting quantum interference device magnetometer measured the magnetic moment to be 24.5 emu. In addition, the Bis/Dex/Fe3O4 nanoparticles were fully dispersed in double-distilled water. Osteoblasts and OCs were individually cultured with the nanoparticles, and an MTT assay revealed that they were non-cytotoxic. An RF system (42 kHz and 450 A) was used to raise the temperature of the nanoparticles for 20 minutes, and the thermal effect was found to be sufficient to destroy OCs. Furthermore, in vivo studies verified that nanoparticles were indeed magnetic resonance imaging contrast agents and that they accumulated after being injected into the body of rats. In conclusion, we developed a water-dispersible magnetic nanoparticle that had RF-induced thermogenic properties, and the results indicated that the Bis/Dex/Fe3O4 nanoparticle had the potential for controlling osteoporosis.

The aims of this study were to establish a rat model of carotid artery injury and to evaluate its suitability for evaluating therapeutic agents active against endothelial proliferation. Wistar-Kyoto rats were injected intravenously with the photochemically reactive dyes rose bengal or Evans blue, and the carotid artery was then focally irradiated with laser light of the appropriate wavelength. Histological sections of the carotid artery were analyzed to determine the appropriate parameters for this model. Ferulic acid was used to assess the suitability of this model for drug screening. No animal died as a result of the photochemical treatment. Endothelial proliferation in the carotid artery was observed in rats injected with rose Bengal and exposed to green laser light. Ferulic acid (400 mg/kg per day) significantly (p

Biocompatible and temperature-sensitive amphiphilic polymeric micelles comprised of poly(succinimide)- g-poly( N-isopropylacrylamide- co-N, N-dimethylacrylamide) (PSI- g-poly(NIPAAm- co-DMAAm)) were synthesized to use as new drug carriers. The PSI- co-poly(PNIPAAm- co-DMAAm) polymers were prepared by nucleophilic opening of poly(succinimide) using amino-terminated poly(NIPAAm- co-DMAAm). The lower critical solution temperature of the copolymer was 40.6℃ higher than normal human body temperature. The blank polymeric micelles were observed to have a regular spherical shape, and the particle sizes were approximately 85 nm. This copolymer exhibited no significant cytotoxicity and hemolysis indicated that the micelles had good biocompatibility. In addition, these polymeric micelles encapsulated the anti-inflammatory drug, hesperetin, in the inner core with a drug loading content of approximately 20%. The release profiles of hesperetin showed a significant temperature-sensitive switching behavior. The hesperetin release response was dramatically lower at a temperature below the lower critical solution temperature as compared with a temperature above the lower critical solution temperature. The lipopolysaccharide-induced nitric oxide production inhibition experiments demonstrated that hesperetin-encapsulated micelles showed a significant reduction. In this study, the biocompatible temperature-sensitive micelles based on PSI- g-poly(NIPAAm- co-DMAAm) have great potential to act as a suitable carrier for drug delivery.

The purpose of this work is to modify hesperetin on nanoparticles of Fe 3 O 4 to form a compound of Fe 3 O 4 /hesperetin, where hesperetin is drug and the Fe 3 O 4 is carrier. The particles of Fe 3 O 4 were synthesized by co-precipitation of Fe (III) and Fe (II) with sodium hydroxide. X-ray diffraction (XRD) was used to study the types of the synthesized iron oxide particles. The XRD pattern confirmed that the synthesized particles are mainly Fe 3 O 4 . Scanning electron microscopy shows the particle size of Fe 3 O 4 is about 14 nm on average. The Fe 3 O 4 /hesperetin compound was synthesized by mixing hesperetin and the Fe 3 O 4 nano-particles in phosphate buffer solution with the cross-linking agents of EDC and NHS. Fourier transform infrared spectroscopy proved that hesperetin is linked with the Fe 3 O 4 nano-particles. Thermal gravimetric analysis demonstrates that the weight ratio of hesperetin with respect to the Fe 3 O 4 /hesperetin compound is about 23.7%. The measured thermal changes of the Fe 3 O 4 nano-particles and the Fe 3 O 4 /hesperetin compound by radio frequency exposure for 60 minutes are 2.3 and 6.5 °C, respectively.