With technological advances in basic research, the intricate mechanism of secondary delayed spinal cord injury (SCI) continues to unravel at a rapid pace. However, despite our deeper understanding of the molecular changes occurring after initial insult to the spinal cord, the cure for paralysis remains elusive. Current treatment of SCI is limited to early administration of high dose steroids to mitigate the harmful effect of cord edema that occurs after SCI and to reduce the cascade of secondary delayed SCI. R ecent evident-based clinical studies have cast doubt on the clinical benefit of steroids in SCI and intense focus on stem cell-based therapy has yielded some encouraging results. An array of mesenchymal stem cells (MSCs) from various sources with novel and promising strategies are being developed to improve function after SCI. In this review, we briefly discuss the pathophysiology of spinal cord injuries and characteristics and the potential sources of MSCs that can be used in the treatment of SCI. We will discuss the progress of MSCs application in research, focusing on the neuroprotective properties of MSCs. Finally, we will discuss the results from preclinical and clinical trials involving stem cell-based therapy in SCI. Core tip: Despite our deeper understanding of the molecular changes that occurs after the spinal cord injury (SCI), the cure for paralysis remains elusive. In this review, the pathophysiology of SCI and characteristics and potential sources of mesenchymal stem cells (MSCs) that can be used in the treatment of SCI were discussed. We also discussed the progress of application of MSCs in research focusing on the neuroprotective properties of MSCs. Finally, we discussed the results from preclinical and clinical trials involving stem cell-based therapy in SCI.

SUMMARY Oxytocin is a hormone with various actions. Oxytocin-containing parvocellular neurons project to the brainstem and spinal cord. Oxytocin release from these neurons suppresses nociception of inflammatory pain, the molecular mechanism of which remains unclear. Here, we report that the noxious stimulus receptor, TRPV1, is an ionotropic oxytocin receptor. Oxytocin elicits TRPV1 activity in native and heterologous expression systems, irrespective of the presence of the classical oxytocin receptor. In TRPV1 knockout mice, DRG neurons exhibit reduced oxytocin sensitivity relative to controls, and oxytocin injections significantly attenuate capsaicin-induced nociception in in vivo experiments. Furthermore, oxytocin potentiates TRPV1 in planar lipid bilayers, supporting a direct agonistic action. Molecular modeling and simulation experiments provide insight into oxytocin-TRPV1 interactions, which resemble RTX/DkTx. Together our findings suggest the existence of endogenous regulatory pathways that modulate nociception via direct action of oxytocin on TRPV1, implying its analgesic effect via channel desensitization.

It has been suggested that the beneficial effects of reperfusing the myocardium might be in part reversed by the occurrence of reperfusion injury. Oxidative stress was suggested to be implicating in the pathogenesis of ischemia-reperfusion (I/R) injury. Many antioxidative plants were shown to be cardioprotective in experimental models of myocardial ischemia-reperfusion (I/R) injury. The present study was designed to investigate the effects of pretreatment with alcoholic extract of Tinospora cordifolia in an in vivo rat model. The model adopted was that of surgically-induced myocardial ischemia, performed by means of left anterior descending coronary artery occlusion (LAD) for 30 min followed by reperfusion for another 4 h. Infarct size was measured by using the staining agent TTC (2,3,5-triphenyl tetrazolium chloride). Lipid peroxide levels in serum and in heart tissue were estimated spectrophotometrically by the methods developed by Yagi and Ohkawa et al. respectively. A lead II electrocardiogram was monitored at various intervals throughout the experiment. A dose dependent reduction in infarct size and in lipid peroxide levels of serum and heart tissue were observed with the prior treatment of T. cordifolia with various doses for 7 d compared to control animals. Hence, the present study suggests the cardioprotective activity of T. cordifolia in limiting ischemia-reperfusion induced myocardial infarction.

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BackgroundInvolvement of MMP-9, uPAR and cathepsin B in adhesion, migration, invasion, proliferation, metastasis and tumor growth has been well established. In the present study, MMP-9, uPAR and cathepsin B genes were downregulated in glioma xenograft cells using shRNA plasmid constructs and we evaluated the involvement of integrins and changes in their adhesion, migration and invasive potential.Methodology/Principal FindingsMMP-9, uPAR and cathepsin B single shRNA plasmid constructs were used to downregulate these molecules in xenograft cells. We also used MMP-9/uPAR and MMP-9/cathepsin B bicistronic constructs to evaluate the cumulative effects. MMP-9, uPAR and cathepsin B downregulation significantly inhibits xenograft cell adhesion to several extracellular matrix proteins. Treatment with MMP-9, uPAR and cathepsin B shRNA of xenografts led to the downregulation of several alpha and beta integrins. In all the assays, we noticed more prominent effects with the bicistronic plasmid constructs when compared to the single plasmid shRNA constructs. FACS analysis demonstrated the expression of αVβ3, α6β1 and α9β1 integrins in xenograft cells. Treatment with bicistronic constructs reduced αVβ3, α6β1 and α9β1 integrin expressions in xenograft injected nude mice. Migration and invasion were also inhibited by MMP-9, uPAR and cathepsin B shRNA treatments as assessed by spheroid migration, wound healing, and Matrigel invasion assays. As expected, bicistronic constructs further inhibited the adhesion, migration and invasive potential of the xenograft cells as compared to individual treatments.Conclusions/SignificanceDownregulation of MMP-9, uPAR and cathespin B alone and in combination inhibits adhesion, migration and invasive potential of glioma xenografts by downregulating integrins and associated signaling molecules. Considering the existence of integrin inhibitor-resistant cancer cells, our study provides a novel and effective approach to inhibiting integrins by downregulating MMP-9, uPAR and cathepsin B in the treatment of glioma.

This study highlights the possible pathological role of MMP-12 in the context of ischemic stroke. Male rats were subjected to a two-hour middle cerebral artery occlusion (MCAO) procedure. MMP-12 shRNA expressing plasmid formulation was administered to these rats twenty-four hours after reperfusion. The results showed a predominant upregulation of MMP-12 (approximately 47, 58, 143, and 265 folds on days 1, 3, 5, 7 post-ischemia, respectively) in MCAO subjected rats. MMP-12 expression was localized to neurons, oligodendrocytes and microglia, but not astrocytes. Transcriptional inactivation of MMP-12 significantly reduced the infarct size. The percent infarct size was reduced from 62.87 ± 4.13 to 34.67 ± 5.39 after MMP-12 knockdown compared to untreated MCAO subjected rats. Expression of myelin basic protein was increased, and activity of MMP-9 was reduced in ischemic rat brains after MMP-12 knockdown. Furthermore, a significant reduction in the extent of apoptosis was noticed after MMP-12 knockdown. TNFα expression in the ipsilateral regions of MCAO-subjected rats was reduced after MMP-12 knockdown in addition to the reduced protein expression of apoptotic molecules that are downstream to TNFα signaling. Specific knockdown of MMP-12 after focal cerebral ischemia offers neuroprotection that could be mediated via reduced MMP-9 activation and myelin degradation as well as inhibition of apoptosis.

T he blood-brain barrier (BBB) is formed by the endothelial cells of cerebral microvessels, which are distinguished from peripheral endothelial cells by their lack of fenestrations, minimal pinocytotic activity, and the tight junctions (TJs).1 In addition to endothelial cells, the BBB is composed of pericytes, astrocytes, neurons, and extracellular matrix.2 Endothelial cells and pericytes are surrounded by the extracellular matrix, which is composed of structural proteins, such as collagen type-IV, laminin, fibronectin, elastin, thrombospondin, and various proteoglycans. The TJs between the endothelial cells of the cerebral microvessels serve to restrict blood-borne substances from entering the brain. The BBB thus provides a dynamic interface between the peripheral circulation and the brain.BBB disruption is an important contributing factor to brain injury that occurs after ischemic stroke. The expression of matrix metalloproteinases (MMPs) in the normal adult brain is very low or undetectable. In the injured brain, MMPs are expressed in various cell types, including resident and infiltrating inflammatory cells.3 However, the brain regions and cellular sources of expression differ for the specific MMPs, as well as the type, severity, and duration of injuries. 4 Ischemia leads to induction of MMPs, which contribute to BBB extracellular matrix degradation. The induction of these MMPs may further perpetuate BBB TJ permeability, thereby leading to BBB leakage, leukocyte infiltration, brain edema, and hemorrhage.2 MMP-2 and MMP-9 are considered the central mediators of ischemic BBB disruption because of their ability to degrade components of microvascular basal lamina, especially collagen type-IV, and to disrupt TJ proteins. [5][6][7][8] Recent investigations highlighted the possible pathological role for MMP-12 in the context of ischemic stroke. 9,10 MMP-12 is upregulated several fold higher than any other MMPs tested after focal cerebral ischemia, and its suppression attenuated the ischemic brain damage.10 Also, MMP-12 is reported to activate other MMPs, such as pro-MMP-2 and Background and Purpose-Matrix metalloproteinases (MMPs) have a central role in compromising the integrity of the blood-brain barrier (BBB). The role of MMP-12 in brain damage after ischemic stroke remains unknown. The main objective of the current study is to investigate the effect of MMP-12 suppression at an early time point before reperfusion on the BBB damage in rats. Methods-Sprague-Dawley rats were subjected to middle cerebral artery occlusion and reperfusion. MMP-12 shRNAexpressing plasmids formulated as nanoparticles were administered at a dose of 1 mg/kg body weight. The involvement of MMP-12 on BBB damage was assessed by performing various techniques, including Evans blue dye extravasation, 2,3,5-triphenyltetrazolium chloride staining, immunoblot, gelatin zymography, and immunofluorescence analysis. Results-MMP-12 is upregulated ≈31-, 47-, and 66-fold in rats subjected 1-, 2-, or 4-hour ischemia, respectively, followed by 1-day reperf...

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