The Neuroprotective Effect of Isotetrandrine on Parkinson's Disease via Anti-Inflammation and Antiapoptosis In Vitro and In Vivo

Parkinson's disease (PD) is one of the most influential diseases in the world, and the current medication only can relieve the clinical symptoms but not slow the progression of PD. Therefore, we intend to examine the neuroprotective activity of plant-derived compound isotetrandrine (ITD) in vitro and in vivo. In vitro, cells were cotreated with ITD and LPS to detect the inflammatory-related protein and mRNA. In vivo, zebrafish were pretreated with ITD and inhibitors prior to 6-OHDA treatment. Then, the behavior was monitored at 5 dpf. Our result showed ITD inhibited LPS-induced upregulation of iNOS, COX-2 protein expression, and iL-6, inos, cox-2, and cd11b mRNA expression in BV2 cells. The data in zebrafish also demonstrated a significant improvement of ITD on the 6-OHDA-induced locomotor deficiency. ITD also improved 6-OHDA-induced apoptosis in zebrafish PD. We also pharmacologically validated the mechanism with three inhibitors, including LY294002, PI3K inhibitor; LY32141996, ERK inhibitor, SnPP, and HO-1 inhibitors. All of these inhibitors could abolish the neuroprotective effect of ITD partially in locomotor activity. Besides, the molecular level also showed the same trend. Treatment of these inhibitors could significantly abolish ITD-induced antineuroinflammatory and antioxidative stress effects in zebrafish PD. Our study showed ITD possessed a neuroprotective activity in zebrafish PD. The mRNA level also supported our arguments. The neuroprotection of ITD might be through antineuroinflammation and antiapoptosis pathways via PI3K, ERK, and HO-1.

Relationship between Q-Tip Test and Urethral Hypermobility on Perineal Ultrasound

BACKGROUND

The aim of this study was to assess the correlation between the overall rest-stress distance measured by transperineal ultrasound (TPUS) and Q-tip test angle in women with urodynamic stress incontinence (USI), and determine a cut-off value of rest-stress distance for predicting urethral hypermobility (UH).

METHODS

Women with USI scheduled for mid-urethral sling surgery were retrospectively recruited. UH was defined as a Q-tip angle more than or equal to 30 degrees. Ultrasonic measurement of the overall rest-stress distance was defined as the linear distance of bladder-neck position change from resting status to maximal strain.

RESULTS

Among the 132 enrolled women, the Pearson correlation coefficient between the overall rest-stress distance in TPUS and Q-tip test angle was 0.9104 (95% CI, 0.8758-0.9357, p < 0.001). In receiver-operating-characteristic-curve analysis, a rest-stress distance of more than 13.3 mm was an optimal cut-off value to predict UH (sensitivity = 76.47%, specificity = 93.3%; area = 0.937, 95% confidence interval: 0.881-0.972).

CONCLUSIONS

The overall rest-stress distance in TPUS correlated well with the Q-tip test angle, indicating that it can be an alternative method for the assessment of USI. A rest-stress distance of more than 13.3 mm was an optimal cut-off value to predict UH in women with USI.

A Major Diplotaxis harra-Derived Bioflavonoid Glycoside as a Protective Agent against Chemically Induced Neurotoxicity and Parkinson's Models; In Silico Target Prediction; and Biphasic HPTLC-Based Quantification

Oxidative stress and chronic inflammation have a role in developing neurodegenerative diseases such as Parkinson’s disease (PD) and inflammatory movement disorders such as rheumatoid arthritis that affect millions of populations. In searching for antioxidant and anti-inflammatory molecules from natural sources that can counteract neurodegenerative diseases and arthritis, the flavonoid-rich extract of Diplotaxis harra (DHE) was selected based on its in vitro antioxidant and anti-inflammatory activities. DHE could inhibit the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions in the lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages from 100% to the level of 28.51 ± 18.67 and 30.19 ± 5.00% at 20 μg/mL, respectively. A TLC bioautography of DHE fractions using 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) led to the isolation of a major antioxidant compound which was identified by X-ray diffraction analysis as isorhamnetin-3-O-β-D-glucoside (IR3G). IR3G also exhibited a potent anti-inflammatory activity, particularly by suppressing the upregulation of iNOS expression, similar to that of dexamethasone (DEX) at 10 μM to the level of 35.96 ± 7.80 and 29.34 ± 6.34%, respectively. Moreover, IR3G displayed a strong neuroprotectivity (>60% at 1.0−4−1.0−3 μM) against 6-hydroxydopamine (6-OHDA)-challenged SHSY5Y neuroblastoma, an in vitro model of dopaminergic neurons for Parkinson’s disease (PD) research. Accordingly, the in vivo anti-Parkinson potentiality was evaluated, where it was found that IR3G successfully reversed the 6-OHDA-induced locomotor deficit in a zebrafish model. A study of molecular docking and molecular dynamic (MD) simulation of IR3G and its aglycone isorhamnetin (IR) against human acetylcholine esterase (AChE), monoamine oxidase B (MAO-B), and Polo-like kinase-2 (PLK2) was performed and further outlined a putative mechanism in modulating neurodegenerative diseases such as PD. The free radical scavenging, anti-inflammatory through anti-iNOS and anti-COX-2 expression, and neuroprotective activities assessed in this study would present partial evidence for the potentiality of D. harra-derived IR3G as a promising natural therapeutic agent against neurodegenerative diseases and inflammatory arthritis. Finally, a biphasic HPTLC method was developed to estimate the biomarker IR3G in D. harra quantitatively.

Antiosteoporosis effects of a marine antimicrobial peptide pardaxin via regulation of the osteogenesis pathway

Antimicrobial peptides (AMPs) are known to play an important role in natural immunity. Moreover, the diverse biological activities of AMPs showed great potency in treating many diseases. Thus, in this study, we used an AMP, that is, pardaxin, from a marine fish (Pardachirus marmoratus), which has been reported to possess antibacterial and antitumor activities. We first investigated the mechanisms of pardaxin in promoting osteogenic differentiation in vitro and in vivo. As per our data, it was determined that pardaxin could stimulate bone morphogenetic protein-2 (BMP-2) and downstream cascade. The activation of BMP-2 could further induce the phosphorylation of Akt and extracellular signal-regulated kinase (ERK). Additionally, the activation of p-Akt and p-ERK could prompt the elevation and translocation of runt-related transcription factor 2 (runx-2), which is associated with osteoblast differentiation. The translocation of runx-2 initiated transcription and translation of osteogenesis-related markers, including alkaline phosphatase (ALP), osterix, and osteocalcin. Pardaxin significantly facilitated preosteoblast cells in mineralization and reversed dexamethasone- (DM-) induced zebrafish bone formation deficiency by activating the osteogenesis pathway. Therefore, we suggest that pardaxin could be a possible candidate for osteoporosis treatment and a promising therapeutic agent.

Effects of Streptococcus thermophilus on anterior cruciate ligament transection-induced early osteoarthritis in rats

Osteoarthritis (OA) is the most common joint disorder and is classically defined as a progressively degenerative disease of articular cartilage. It manifests as joint pain and disability and currently has no comprehensive treatments. The primary purpose of the present study was to test the effects of probiotics, Streptococcus thermophilus (TCI633), on anterior cruciate ligament transection (ACLT)-induced experimental osteoarthritis (OA) in rats. In the current study, the experimental groups were given TCI633 (5x10⁹, 5x10¹⁰ and 5x10¹¹ CFU/kg/day) and glucosamine sulfate (250 mg/kg) between week 8 and 20 following ACLT. The results showed that oral administration of TCI633 and glucosamine had significant therapeutic effects on pain behaviors and knee swelling. Dose-dependent effects of TCI633 were also observed in ACLT-treated rats. Histopathological analysis demonstrated that ACLT+TCI633 (5x10⁹, 5x10¹⁰ and 5x10¹¹ CFU/kg/day) improved the synovial inflammation and cartilage damage of ACLT rats. Histology evaluation using the Osteoarthritis Research Society International system and synovial inflammatory score analysis showed the dose-dependent inhibition of TCI633 on synovial inflammation and cartilage damage. Immunohistochemical staining and TUNEL apoptosis staining showed that TCI633 could effectively increase the expression of type II collagen and reduce the amount of chondrocyte apoptosis in cartilage. Therefore, the present study demonstrated that oral intake of TCI633 could significantly suppressing pain behavior, reduce joint swelling and synovial tissue inflammation and increase type II collagen expression in cartilage. There was also a reduction in chondrocyte apoptosis and decreased progression of OA in ACLT-treated rats.

Etoricoxib prevents progression of osteolysis in repeated intra-articular monosodium urate-induced gouty arthritis in rats

Deposition of monosodium urate (MSU) crystals in the joint or synovium is the major factor in Gouty arthritis (GA). The clinical features of chronic and recurrent GA include pain and the subsequent development of chronic tophaceous GA with multiple tophi deposits accompanied by osteolysis. The majority of previous animal studies have focused on MSU-induced acute GA without making observations regarding osteolysis. In the study, intra-articular injections of MSU into the knee (2 times/week for 10 weeks) was used to induce chronic and recurrent attacks of GA that in turn induced progressive osteolysis. Moreover, we also evaluated whether the clinical, nonsteroidal anti-inflammatory drug (NSAID) etoricoxib attenuated the osteoclastogenesis of progressive osteolysis. The knee morphometry and the expression of osteoclastogenesis-related proteins (cathepsin K and matrix metalloproteinase-9 and -13) in the knee were examined by micro-CT and immunohistochemistry, respectively. Results showed that oral etoricoxib not only significantly attenuated the nociceptive behaviors of the rats but that it also inhibited the expression of osteoclastogenesis-related proteins in their knee joints in chronic and recurrent attacks of GA. Our findings thus suggest that NSAIDs not only inhibit nociception but also prevent the progression of osteolysis in chronic and repeated attacks of GA.

Therapeutic Role of Protein Tyrosine Phosphatase 1B in Parkinson's Disease via Antineuroinflammation and Neuroprotection In Vitro and In Vivo

Parkinson's disease (PD) is one of the most widespread neurodegenerative diseases. However, the currently available treatments could only relieve symptoms. Novel therapeutic targets are urgently needed. Several previous studies mentioned that protein tyrosine phosphatase 1B (PTP1B) acted as a negative regulator of the insulin signal pathway and played a significant role in the inflammation process. However, few studies have investigated the role of PTP1B in the central nervous system. Our study showed that suramin, an inhibitor of PTP1B, could improve neuronal damage. It could significantly attenuate the interferon-gamma-induced upregulation of proinflammatory cytokines, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). It enhanced M2 type microglia markers, such as arginase-1 and Ym-1 in BV2 murine microglial cells. PTP1B inhibition also reversed 6-hydroxydopamine- (6-OHDA-) induced downregulation of phospho-cAMP response element-binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF) in SH-SY5Y cells. Besides, we knocked down and overexpressed PTP1B in the SH-SY5Y cells to confirm its role in neuroprotection. We also verified the effect of suramin in the zebrafish PD model. Treatment with suramin could significantly reverse 6-OHDA-induced locomotor deficits and improved tyrosine hydroxylase (TH) via attenuating endoplasmic reticulum (ER) stress biomarkers. These results support that PTP1B could potentially regulate PD via antineuroinflammation and antiapoptotic pathways.

Therapeutic Effect of Modulating TREM-1 via Anti-inflammation and Autophagy in Parkinson's Disease

Parkinson’s disease (PD) is one of the most common age-related neurodegenerative diseases, and neuroinflammation has been identified as one of its key pathological characteristics. Triggering receptors expressed on myeloid cells-1 (TREM-1) amplify the inflammatory response and play a role in sepsis and cancer. Recent studies have demonstrated that the attenuation of TREM-1 activity produces cytoprotective and anti-inflammatory effects in macrophages. However, no study has examined the role of TREM-1 in neurodegeneration. We showed that LP17, a synthetic peptide blocker of TREM-1, significantly inhibited the lipopolysaccharide (LPS)-induced upregulation of proinflammatory cascades of inducible nitric oxide synthase (iNOS), cyclooxygenase-2, and nuclear factor-kappa B. Moreover, LP17 enhanced the LPS-induced upregulation of autophagy-related proteins such as light chain-3 and histone deacetylase-6. We also knocked down TREM-1 expression in a BV2 cell model to further confirm the role of TREM-1. LP17 inhibited 6-hydroxydopamine-induced locomotor deficit and iNOS messenger RNA expression in zebrafish. We also observed therapeutic effects of LP17 administration in 6-hydroxydopamine-induced PD syndrome using a rat model. These data suggest that the attenuation of TREM-1 could ameliorate neuroinflammatory responses in PD and that this neuroprotective effect might occur via the activation of autophagy and anti-inflammatory pathways.

Therapeutic Effect of Platelet-Rich Plasma in Rat Spinal Cord Injuries

Platelet-rich plasma (PRP) is prepared by centrifuging fresh blood in an anticoagulant state, and harvesting the platelet-rich portion or condensing platelets. Studies have consistently demonstrated that PRP concentrates are an abundant source of growth factors, such as platelet-derived growth factor (PDGF), transforming growth factor β (TGF-β), insulin-like growth factor 1 (IGF-1), and epithelial growth factor (EGF). The complex mechanisms underlying spinal cord injury (SCI) diminish intrinsic repair and neuronal regeneration. Several studies have suggested that growth factor-promoted axonal regeneration can occur for an extended period after injury. More importantly, the delivery of exogenous growth factors contained in PRP, such as EGF, IGF-1, and TGF-β, has neurotrophic effects on central nervous system (CNS) injuries and neurodegenerative diseases. However, only a few studies have investigated the effects of PRP on CNS injuries or neurodegenerative diseases. According to our review of relevant literature, no study has investigated the effect of intrathecal (i.t.) PRP injection into the injured spinal cord and activation of intrinsic mechanisms. In the present study, we directly injected i.t. PRP into rat spinal cords and examined the effects of PRP on normal and injured spinal cords. In rats with normal spinal cords, PRP induced microglia and astrocyte activation and PDGF-B and ICAM-1 expression. In rats with SCIs, i.t. PRP enhanced the locomotor recovery and spared white matter, promoted angiogenesis and neuronal regeneration, and modulated blood vessel size. Furthermore, a sustained treatment (a bolus of PRP followed by a 1/3 dose of initial PRP concentration) exerted more favorable therapeutic effects than a single dose of PRP. Our findings suggest by i.t. PRP stimulate angiogenesis, enhancing neuronal regeneration after SCI in rats. Although PRP induces minor inflammation in normal and injured spinal cords, it has many advantages. It is an autologous, biocompatible, nontoxic material that does not result in a major immune response. In addition, based on its safety and ease of preparation, we hypothesize that PRP is a promising therapeutic agent for SCI.

Nucleophosmin modulates the alleviation of atopic dermatitis caused by the marine-derived compound dihydroaustrasulfone alcohol

Atopic dermatitis (AD) is a chronic inflammatory skin disease, and its prevalence is increasing. AD usually elicits skin barrier dysfunction, dry skin and itching. As the mechanisms of AD remain unknown, there is an urgent need to find effective therapies. Because of the diversity and complexity of marine environments, the discovery of drugs from marine organisms as novel therapeutic agents for human diseases has seen renewed interest. Dihydroaustrasulfone alcohol (WA-25), the synthetic precursor of austrasulfone, which is a natural product isolated from a Formosan soft coral, has been shown to possess many therapeutic effects in our previous studies. However, the detailed mechanisms and therapeutic effects of WA-25 on AD are incompletely understood. We performed in vitro and in vivo studies to examine the effects of WA-25 on AD. We showed that WA-25 blocks inflammation and oxidative stress. Simultaneously, we also found that WA-25 reduces the AD scores and AD-induced transepidermal water loss (TEWL), scratching behavior, and alloknesis. WA-25 is more effective in cases of AD than are the drugs that are currently used clinically. Importantly, we also found that when nucleophosmin (NPM) was inhibited or when its expression was reduced, the anti-inflammatory and anti-AD effects of WA-25 were blocked. These data suggest that NPM plays dual roles in inflammation and AD. Overall, these results suggest that WA-25 is a potential anti-inflammatory and AD therapeutic agent that is modulated by NPM.

MSP-4, an Antimicrobial Peptide, Induces Apoptosis via Activation of Extrinsic Fas/FasL- and Intrinsic Mitochondria-Mediated Pathways in One Osteosarcoma Cell Line

Osteosarcoma (OS) is a common malignant bone cancer. The relatively high density of a person's bone structure means low permeability for drugs, and so finding drugs that can be more effective is important and should not be delayed. MSPs are marine antimicrobial peptides (AMP) and natural compounds extracted from Nile tilapia (Oreochromis niloticus). MSP-4 is a part of the AMPs series, with the advantage of having a molecular weight of about 2.7-kDa and anticancer effects, although the responsible anticancer mechanism is not very clear. The goal of this study is to determine the workings of the mechanism associated with apoptosis resulting from MSP-4 in osteosarcoma MG63 cells. The study showed that MSP-4 significantly induced apoptosis in MG63 cells, with Western blot indicating that MSP-4 induced this apoptosis through an intrinsic pathway and an extrinsic pathway. Thus, a pretreatment system with a particular inhibitor of Z-IETD-FMK (caspase-8 inhibitor) and Z-LEHD-FMK (caspase-9 inhibitor) significantly attenuated the cleavage of caspase-3 and prevented apoptosis. These observations indicate that low concentrations of MSP-4 can help induce the apoptosis of MG63 through a Fas/FasL- and mitochondria-mediated pathway and suggest a potentially innovative alternative to the treatment of human osteosarcoma.

Potentiation of spinal glutamatergic response in the neuron-glia interactions underlies the intrathecal IL-1β-induced thermal hyperalgesia in rats

AIMS

We previously demonstrated that intrathecal IL-1β upregulated phosphorylation of p38 mitogen-activated protein kinase (P-p38 MAPK) and inducible nitric oxide synthase (iNOS) in microglia and astrocytes in spinal cord, increased nitric oxide (NO) release into cerebrospinal fluid, and induced thermal hyperalgesia in rats. This study investigated the role of spinal glutamatergic response in intrathecal IL-1β-induced nociception in rats.

METHODS

The pretreatment effects of MK-801 (5 μg), minocycline (20 μg), and SB203580 (5 μg) on intrathecal IL-1β (100 ng) in rats were measured by behavior, Western blotting, CSF analysis, and immunofluorescence studies.

RESULTS

IL-1β increased phosphorylation of NR-1 (p-NR1) subunit of N-methyl-D-aspartate receptors in neurons and microglia, reduced glutamate transporters (GTs; glutamate/aspartate transporter by 60.9%, glutamate transporter-1 by 55.0%, excitatory amino acid carrier-1 by 39.8%; P<.05 for all), and increased glutamate (29%-133% increase from 1.5 to 12 hours; P<.05) and NO (44%-101% increase from 4 to 12 hours; P<.05) levels in cerebrospinal fluid. MK-801 significantly inhibited all the IL-1β-induced responses; however, minocycline and SB203580 blocked the IL-1β-downregulated GTs and elevated glutamate but not the upregulated p-NR1.

CONCLUSION

The enhanced glutamatergic response and neuron-glia interaction potentiate the intrathecal IL-1β-activated P-p38/iNOS/NO signaling and thermal hyperalgesia.

A Coral-Derived Compound Improves Functional Recovery after Spinal Cord Injury through Its Antiapoptotic and Anti-Inflammatory Effects

Background: Our previous in vitro results demonstrated that 11-dehydrosinulariolide significantly reduced 6-hydroxydopamine-induced cytotoxicity and apoptosis in a human neuroblastoma cell line, SH-SY5Y, and suppressed the expression of inducible NO synthase (iNOS) and cyclooxygenase 2 in lipopolysaccharide-stimulated macrophage cells. The neuroprotective and anti-inflammatory effects of 11-dehydrosinulariolide may be suitable for treating spinal cord injury (SCI). Methods: In the present study, Wistar rats were pretreated with 11-dehydrosinulariolide or saline through intrathecal injection after a thoracic spinal cord contusion injury induced using a New York University (NYU) impactor. The apoptotic cells were assessed using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expression and localization of proinflammatory, apoptosis-associated and cell survival-related pathway proteins were examined through immunoblotting and immunohistochemistry. Results: 11-Dehydrosinulariolide attenuated SCI-induced cell apoptosis by upregulating the antiapoptotic protein Bcl-2 and cell survival-related pathway proteins p-Akt and p-ERK, 8 h after SCI. Furthermore, the transcription factor p-CREB, which regulates Bcl-2 expression, was upregulated after 11-dehydrosinulariolide treatment. On day 7 after SCI, 11-dehydrosinulariolide exhibited an anti-inflammatory effect, attenuating SCI-induced upregulation of the inflammatory proteins iNOS and tumor necrosis factor-α. 11-Dehydrosinulariolide also induced an increase in the expression of arginase-1 and CD206, markers of M2 microglia, in the injured spinal cord on day 7 after SCI. Thus, the anti-inflammatory effect of 11-dehydrosinulariolide may be related to the promotion of an alternative pathway of microglia activation. Conclusion: The results show that 11-dehydrosinulariolide exerts antiapoptotic effects at 8 h after SCI and anti-inflammatory effects at 7 days after SCI. We consider that this compound may be a promising therapeutic agent for SCI.

Contributions of p38 and ERK to the antinociceptive effects of TGF-β1 in chronic constriction injury-induced neuropathic rats

Background

Transforming growth factor-βs (TGF-βs) are a group of multifunctional proteins that have neuroprotective roles in various experimental models. We previously reported that intrathecal (i.t.) injections of TGF-β1 significantly inhibit neuropathy-induced thermal hyperalgesia, spinal microglia and astrocyte activation, as well as upregulation of tumor necrosis factor-α. However, additional cellular mechanisms for the antinociceptive effects of TGF-β1, such as the mitogen-activated protein kinase (MAPK) pathway, have not been elucidated. During persistent pain, activation of MAPKs, especially p38 and extracellular signal-regulated kinase (ERK), have crucial roles in the induction and maintenance of pain hypersensitivity, via both nontranscriptional and transcriptional regulation. In the present study, we used a chronic constriction injury (CCI) rat model to explore the role of spinal p38 and ERK in the analgesic effects of TGF-β1.

Methods

We investigated the cellular mechanisms of the antinociceptive effects of i.t. injections of TGF-β1 in CCI induced neuropathic rats by spinal immunohistofluorescence analyses.

Results

The results demonstrated that the antinociceptive effects of TGF-β1 (5 ng) were maintained at greater than 50 % of the maximum possible effect in rats with CCI for at least 6 h after a single i.t. administration. Thus, we further examined these alterations in spinal p38 and ERK from 0.5 to 6 h after i.t. administration of TGF-β1. TGF-β1 significantly attenuated CCI-induced upregulation of phosphorylated p38 (phospho-p38) and phosphorylated ERK (phospho-ERK) expression in the dorsal horn of the lumbar spinal cord. Double immunofluorescence staining illustrated that upregulation of spinal phospho-p38 was localized to neurons, activated microglial cells, and activated astrocytes in rats with CCI. Additionally, increased phospho-ERK occurred in activated microglial cells and activated astrocytes. Furthermore, i.t. administration of TGF-β1 markedly inhibited phospho-p38 upregulation in neurons, microglial cells, and astrocytes. However, i.t. injection of TGF-β1 also reduced phospho-ERK upregulation in microglial cells and astrocytes.

Conclusions

The present results demonstrate that suppressing p38 and ERK activity affects TGF-β1-induced analgesia during neuropathy.

The role of the PI3K/Akt/mTOR pathway in glial scar formation following spinal cord injury

Several studies suggest that glial scars pose as physical and chemical barriers that limit neurite regeneration after spinal cord injury (SCI). Evidences suggest that the activation of the PI3K/Akt/mTOR signaling pathway is involved in glial scar formation. Therefore, inhibition of the PI3K/Akt/mTOR pathway may beneficially attenuate glial scar formation after SCI. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) negatively regulates the PI3K/Akt/mTOR pathway. Therefore, we hypothesized that the overexpression of PTEN in the spinal cord will have beneficial effects after SCI. In the present study, we intrathecally injected a recombinant adenovirus carrying the pten gene (Ad-PTEN) to cause overexpression of PTEN in rats with contusion injured spinal cords. The results suggest overexpression of PTEN in spinal cord attenuated glial scar formation and led to improved locomotor function after SCI. Overexpression of PTEN following SCI attenuated gliosis, affected chondroitin sulfate proteoglycan expression, and improved axon regeneration into the lesion site. Furthermore, we suggest that the activation of the PI3K/Akt/mTOR pathway in astrocytes at 3 days after SCI may be involved in glial scar formation. Because delayed treatment with Ad-PTEN enhanced motor function recovery more significantly than immediate treatment with Ad-PTEN after SCI, the results suggest that the best strategy to attenuate glial scar formation could be to introduce 3 days after SCI. This study's findings thus have positive implications for patients who are unable to receive immediate medical attention after SCI.

Involvement of phosphatase and tensin homolog deleted from chromosome 10 in rodent model of neuropathic pain

Background

Many cancer research studies have extensively examined the phosphatase and tensin homolog deleted from chromosome 10 (PTEN) pathway. There are only few reports that suggest that PTEN might affect pain; however, there is still a lack of evidence to show the role of PTEN for modulating pain. Here, we report a role for PTEN in a rodent model of neuropathic pain.

Results

We found that chronic constriction injury (CCI) surgery in rats could elicit downregulation of spinal PTEN as well as upregulation of phosphorylated PTEN (phospho-PTEN) and phosphorylated mammalian target of rapamycin (phospho-mTOR). After examining such changes in endogenous PTEN in neuropathic rats, we explored the effects of modulating the spinal PTEN pathway on nociceptive behaviors. The normal rats exhibited mechanical allodynia after intrathecal (i.t.) injection of adenovirus-mediated PTEN antisense oligonucleotide (Ad-antisense PTEN). These data indicate the importance of downregulation of spinal PTEN for nociception. Moreover, upregulation of spinal PTEN by i.t. adenovirus-mediated PTEN (Ad-PTEN) significantly prevented CCI-induced development of nociceptive sensitization, thermal hyperalgesia, mechanical allodynia, cold allodynia, and weight-bearing deficits in neuropathic rats. Furthermore, upregulation of spinal PTEN by i.t. Ad-PTEN significantly attenuated CCI-induced microglia and astrocyte activation, upregulation of tumor necrosis factor-α (TNF-α) and phospho-mTOR, and downregulation of PTEN in neuropathic rats 14 days post injury.

Conclusions

These findings demonstrate that PTEN plays a key, beneficial role in a rodent model of neuropathic pain.

A novel zebrafish model to provide mechanistic insights into the inflammatory events in carrageenan-induced abdominal edema

A suitable small animal model may help in the screening and evaluation of new drugs, especially those from natural products, which can be administered at lower dosages, fulfilling an urgent worldwide need. In this study, we explore whether zebrafish could be a model organism for carrageenan-induced abdominal edema. The research results showed that intraperitoneal (i.p.) administration of 1.5% λ-carrageenan in a volume of 20 µL significantly increased abdominal edema in adult zebrafish. Levels of the proinflammatory proteins tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthase (iNOS) were increased in carrageenan-injected adult zebrafish during the development of abdominal edema. An associated enhancement was also observed in the leukocyte marker, myeloperoxidase (MPO). To support these results, we further observed that i.p. methylprednisolone (MP; 1 µg), a positive control, significantly inhibited carrageenan-induced inflammation 24 h after carrageenan administration. Furthermore, i.p. pretreatment with either an anti-TNF-α antibody (1∶5 dilution in a volume of 20 µL) or the iNOS-selective inhibitor aminoguanidine (AG; 1 µg) inhibited carrageenan-induced abdominal edema in adult zebrafish. This new animal model is uncomplicated, easy to develop, and involves a straightforward inducement of inflammatory edema for the evaluation of small volumes of drugs or test compounds.

A novel anabolic agent: a simvastatin analogue without HMG-CoA reductase inhibitory activity

For the first time, structural information regarding the role of simvastatin in bone anabolism is described, and a bone-specific statin is introduced. Polyaspartate-conjugated simvastatin was synthesized by solid-phase synthesis with the assistance of microwave irradiation. It displays significant bone targeting and bone formation with less toxicity than simvastatin.

Effects of 6-hydroxydopamine exposure on motor activity and biochemical expression in zebrafish (Danio rerio) larvae

Parkinson's disease (PD) is a neurodegenerative disease that is characterized by the progressive loss of dopaminergic (DA) neurons in the substantia nigra. However, current treatments for PD are mainly palliative. Recently, researchers discovered that neurotoxins can induce Parkinsonian-like symptoms in zebrafish. No study to date has investigated the characteristics of PD, such as neuroinflammation factors, oxidative stress, or ubiquitin dysfunction, in this model. Therefore, the current study was aimed at utilizing commonly used clinical drugs, minocycline, vitamin E, and Sinemet, to test the usefulness of this model. Previous studies had indicated that DA cell loss was greater with 6-hydroxydopamine (6-OHDA) than with other neurotoxins. Thus, we first challenged zebrafish with 6-OHDA immersion and found a significant reduction in zebrafish locomotor activity; we then reversed the locomotor disruptions by treatment with vitamin E, Sinemet, or minocycline. The present study also analyzed the mRNA expression of parkin, pink1, and cd-11b, because the expression of these molecular targets has been shown to result in attenuation in mammalian models of PD. Vitamin E, Sinemet, and minocycline significantly reversed 6-OHDA-induced changes of parkin, pink1, and cd-11b mRNA expression in zebrafish. Moreover, we assessed tyrosine hydroxylase (TH) expression to confirm the therapeutic effects of vitamin E tested on this PD model and established that vitamin E reversed the 6-OHDA-induced damage on TH expression. Our results provide some support for the validity of this in vivo Parkinson's model, and we hope that this model will be more widely used in the future.