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Alzheimer disease (AD) is a progressive neurodegenerative disease, which is characterized by loss of memory and cognitive function. In AD patients dysfunction of the cholinergic system is the main cause of cognitive disorders, and decreased activity of choline acetyltransferase (ChAT), an enzyme responsible for acetylcholine (ACh) synthesis, is observed. In the present study we investigated if brain transplantation of human neural stem cells (NSCs) genetically modified to encode ChAT gene improves cognitive function of kainic acid (KA)-induced learning deficit rats. Intrahippocampal injection of KA to hippocampal CA3 region caused severe neuronal loss, resulting in profound learning and memory deficit. F3.ChAT human NSCs transplanted intracerebroventricularly improved fully the learning and memory function of KA-induced learning deficit animals, in parallel with the elevation of ACh levels in cerebrospinal fluid. F3.ChAT human NSCs migrated to the KA-induced injury site (CA3) and differentiated into neurons and astrocytes. The present study demonstrates that human NSCs expressing ChAT have lesion-tropic property and improve cognitive function of learning deficit model rats with hippocampal injury by increasing ACh level.

Brain ageing leads to atrophy and degeneration of the cholinergic nervous system, resulting in profound neurobehavioral and cognitive dysfunction from decreased acetylcholine biosynthesis and reduced secretion of growth and neurotrophic factors. Human adipose tissue-derived mesenchymal stem cells (ADMSCs) were intravenously (1 3 10 6 cells) or intracerebroventricularly (4 3 10 5 cells) transplanted into the brains of 18-month-old mice once or four times at 2-week intervals. Transplantation of ADMSCs improved both locomotor activity and cognitive function in the aged animals, in parallel with recovery of acetylcholine levels in brain tissues. Transplanted cells differentiated into neurons and, in part, into astrocytes and produced choline acetyltransferase proteins. Transplantation of ADMSCs restored microtubule-associated protein 2 in brain tissue and enhanced Trk B expression and the concentrations of brain-derived neurotrophic factor and nerve growth factor. These results indicate that human ADMSCs differentiate into neural cells in the brain microenvironment and can restore physical and cognitive functions of aged mice not only by increasing acetylcholine synthesis but also by restoring neuronal integrity that may be mediated by growth/neurotrophic factors. V V C 2013 Wiley Periodicals, Inc.

Knockout studies suggest that PTEN limits the regenerative capacities of CNS axons as a dominant antagonist of PI3 kinase, but the transgenic approach is not feasible for treating patients. Although application of bisperoxovanadium may block PTEN function, it is a general inhibitor of phosphotyrosine phosphatases and may target enzymes other than PTEN, causing side effects and preventing firm conclusions about PTEN inhibition on regulating neuronal growth. A pharmacological method to selectively suppress PTEN post-injury could be a valuable strategy for promoting CNS axon regeneration. We identified PTEN antagonist peptides (PAPs) by targeting PTEN critical functional domains and evaluated their efficacy for promoting axon growth. Four PAPs (PAP1-4) bound to PTEN protein expressed in COS7 cells and blocked PTEN signaling in vivo. Subcutaneous administration of PAPs initiated two days after dorsal over-hemisection injury significantly stimulated growth of descending serotonergic fibers in the caudal spinal cord of adult mice. Systemic PAPs induce significant sprouting of corticospinal fibers in the rostral spinal cord and limited growth of corticospinal axons in the caudal spinal cord. More importantly, PAP treatment enhanced recovery of locomotor function in adult rodents with spinal cord injury. This study may facilitate development of effective therapeutic agents for CNS injuries.

Extracellular matrix molecule chondroitin sulfate proteoglycans (CSPGs) are highly upregulated in scar tissues and form a potent chemical barrier for CNS axon regeneration. Recent studies support that the receptor protein tyrosine phosphatase σ (PTPσ) and its subfamily member leukocyte common antigen related phosphatase (LAR) act as transmembrane receptors to mediate CSPG inhibition. PTPσ deficiency increased regrowth of ascending axons into scar tissues and descending corticospinal tract (CST) axons into the caudal spinal cord after spinal cord injury (SCI). Pharmacological LAR inhibition enhanced serotonergic axon growth in SCI mice. However, transgenic LAR deletion on axon growth in vivo and role of LAR in regulating regrowth of other fiber tracts have not been studied. Here, we studied role of LAR in restricting regrowth of injured descending CNS axons in deficient mice. LAR deletion increased regrowth of serotonergic axons into scar tissues and caudal spinal cord after dorsal overhemitransection. LAR deletion also stimulated regrowth of CST fibers into the caudal spinal cord. LAR protein was upregulated days to weeks after injury and co-localized to serotonergic and CST axons. Moreover, LAR deletion improved functional recovery by increasing BMS locomotor scores and stride length and reducing grid walk errors. This is the first transgenic study that demonstrates crucial role of LAR in restricting regrowth of injured CNS axons.

We examined the effects of trans-resveratrol on male reproductive functions; ex-vivo penile erection and in-vivo sperm counts and quality. For the ex-vivo study, the relaxation effects of resveratrol on isolated New Zealand white rabbit corpus cavernosum, precontracted by phenylephrine (5x10(-5) M) were measured. The in-vivo study measured reproductive organ weights, blood testosterone levels, testicular histopathology, sperm counts, as well as the epididymal sperm motility and deformity of male ICR mice given an oral dose of resveratrol (50 mg/ kg) for 28 days. Resveratrol elicited a concentration-dependent relaxing effect on corpus cavernosum, leading to a median effective concentration (EC50) of 0.29 mg/mL. Repeated treatment with resveratrol (50 mg/kg) did not cause an increase in body weight, reproductive organ weight or testicular microscopic findings; however, resveratrol did elicit an increase in blood testosterone concentration, testicular sperm counts and epididymal sperm motility by 51.6%, 15.8% and 23.3%, respectively, without influence on sperm deformity. In conclusion, we propose that resveratrol has a positive effect on male reproductive function by triggering a penile erection, as well as enhancing blood testosterone levels, testicular sperm counts, and epididymal sperm motility.

The gut microbiota is important for maintaining the integrity of the intestinal barrier, promoting immunological tolerance and carrying out metabolic activities that have not evolved in hosts. Intestinal dysbiosis is associated with chronic kidney disease and probiotic supplementation has been shown to be beneficial. However, it is not known whether gut microorganisms-specifically, lactic acid bacteria (LAB) can protect against acute kidney injury (AKI). To address this issue, the present study investigated the effects of Lactobacillus salivarius BP121, an intestinal LAB isolated from the feces of newborns, in a rat model of cisplatin-induced AKI and also in Caco-2 human intestinal epithelial cells. BP121 prevented cisplatin-induced AKI in rats, as demonstrated by decreases in inflammation and oxidative stress in kidney tissue and in serum levels of uremic toxins such as indoxyl sulfate (IS) and p-cresol sulfate (PCS). BP121 also reduced intestinal permeability, as determined using fluorescein isothiocyanate-dextran by immunohistochemical detection of tight junction (TJ) proteins such as zona occludens-1 and occludin. The abundance of Lactobacillus spp., which are beneficial intestinal flora, was increased by BP121; this was accompanied by an increase in the concentrations of short-chain fatty acids in feces. Additionally, H 2 O 2 -induced TJ protein damage was reduced in Caco-2 cells treated with BP121 culture supernatant, an effect that was reversed by the 5' AMP-activated protein kinase (AMPK) inhibitor Compound C and Toll-like receptor (TLR)4 inhibitor TLR4-IN-C34. In conclusion, this study demonstrated that L. salivarius BP121 protects against cisplatin-induced AKI by decreasing inflammation and oxidative stress and this renoprotective effect is partially mediated by modulating the gut environment and thereby suppressing IS and PCS production as well as by regulating AMPK and TLR4 dependent TJ assembly.