Vitamin D Reduces GABA-Positive Astrocytes in the 5xFAD Mouse Model of Alzheimer's Disease.

Background: Vitamin D has neuroprotective and immunomodulating functions that may impact glial cell function in the brain. Previously, we reported molecular and behavioral changes caused by deficiency and supplementation of vitamin D in an Alzheimer's disease (AD) mouse model. Recent studies have highlighted reactive astrocytes as a new therapeutic target for AD treatment. However, the mechanisms underlying the therapeutic effects of vitamin D on the glial cells of AD remain unclear. Objective: To investigate the potential association between vitamin D deficiency/supplementation and the pathological progression of AD, including amyloid-ß (Aß) pathology and reactive astrogliosis. Methods: Transgenic hemizygous 5XFAD male mice were subjected to different dietary interventions and intraperitoneal vitamin D injections to examine the effects of vitamin D deficiency and supplementation on AD. Brain tissue was then analyzed using immunohistochemistry for Aß plaques, microglia, and astrocytes, with quantifications performed via ImageJ software. Results: Our results demonstrated that vitamin D deficiency exacerbated Aß plaque formation and increased GABA-positive reactive astrocytes in AD model mice, while vitamin D supplementation ameliorated these effects, leading to a reduction in Aß plaques and GABA-positive astrocytes. Conclusions: Our findings highlight the significant impact of vitamin D status on Aß pathology and reactive astrogliosis, underscoring its potential role in the prevention and treatment of AD. This study provides the first in vivo evidence of the association between vitamin D and reactive astrogliosis in AD model mice, indicating the potential for targeting vitamin D levels as a novel therapeutic approach for AD.

Vanadium administration ameliorates cortical structural and functional changes in juvenile hydrocephalic mice.

Vanadium is a prevalent neurotoxic transition metal with therapeutic potentials in some neurological conditions. Hydrocephalus poses a major clinical burden in neurological practice in Africa. Its primary treatment (shunting) has complications, including infection and blockage; alternative drug-based therapies are therefore necessary. This study investigates the function and cytoarchitecture of motor and cerebellar cortices in juvenile hydrocephalic mice following treatment with varying doses of vanadium. Fifty juvenile mice were allocated into five groups (n = 10 each): controls, hydrocephalus-only, low- (0.15 mg/kg), moderate- (0.3 mg/kg), and high- (3.0 mg/kg) dose vanadium groups. Hydrocephalus was induced by the intracisternal injection of kaolin and sodium metavanadate administered by intraperitoneal injection 72hourly for 28 days. Neurobehavioral tests: open field, hanging wire, and pole tests, were carried out to assess locomotion, muscular strength, and motor coordination, respectively. The cerebral motor and the cerebellar cortices were processed for cresyl violet staining and immunohistochemistry for neurons (NeuN) and astrocytes (glial fibrillary acidic protein). Hydrocephalic mice exhibited body weight loss and behavioral deficits. Horizontal and vertical movements and latency to fall from hanging wire were significantly reduced, while latency to turn and descend the pole were prolonged in hydrocephalic mice, suggesting impaired motor ability; this was improved in vanadium-treated mice. Increased neuronal count, pyknotic cells, neurodegeneration and reactive astrogliosis were observed in the hydrocephalic mice. These were mostly mitigated in the vanadium-treated mice, except in the high-dose group where astrogliosis persisted. These results demonstrate a neuroprotective potential of vanadium administration in hydrocephalus. The molecular basis of these effects needs further exploration.

Taurine supplementation improves hippocampal metabolism in immature rats with intrauterine growth restriction (IUGR) through protecting neurons and reducing gliosis.

Taurine as an essential amino acid in the brain could play an important role in protecting the fetal brain of intrauterine growth restriction (IUGR). The hippocampus with IUGR showed neural metabolic disorder and structure changed that affected memory and learning ability. This study was aimed to identify the effect of taurine supplementation on the metabolism alterations and cellular composition changes of the hippocampus in IUGR immature rats. Metabolite concentrations were determined by magnetic resonance spectroscopy (MRS) in the hippocampus of juvenile rats with IUGR following taurine supplementation with antenatal or postnatal supply. The composition of neural cells in the hippocampus was observed by immunohistochemical staining (IHC) and western blotting (WB). Antenatal taurine supplementation increased the ratios of N-acetylaspartate (NAA) /creatine (Cr) and glutamate (Glu) /Cr of the hippocampus in the IUGR immature rats, but reduced the ratios of choline (Cho) /Cr and myoinositol (mI) /Cr. At the same time, the protein expression of NeuN in the IUGR rats was increased through intrauterine taurine supplementation, and the GFAP expression was reduced. Especially the effect of antenatal taurine was better than postpartum. Furthermore, there existed a positive correlation between the NAA/Cr ratio and the NeuN protein expression (R = 0.496 p < 0.001 IHC; R = 0.568 p < 0.001 WB), the same results existed in the relationship between the mI/Cr ratio and the GFAP protein expression (R = 0.338 p = 0.019 IHC; R = 0.440 p = 0.002 WB). Prenatal taurine supplementation can better improve hippocampal neuronal metabolism by increasing NAA / Cr ratio related to the number of neurons and reducing Cho / Cr ratio related to the number of glial cells.

The Mechanisms Underlying the Protective Action of Selenium Nanoparticles against Ischemia/Reoxygenation Are Mediated by the Activation of the Ca2+ Signaling System of Astrocytes and Reactive Astrogliosis.

In recent years, much attention has been paid to the study of the therapeutic effect of the microelement selenium, its compounds, especially selenium nanoparticles, with a large number of works devoted to their anticancer effects. Studies proving the neuroprotective properties of selenium nanoparticles in various neurodegenerative diseases began to appear only in the last 5 years. Nevertheless, the mechanisms of the neuroprotective action of selenium nanoparticles under conditions of ischemia and reoxygenation remain unexplored, especially for intracellular Ca2+ signaling and neuroglial interactions. This work is devoted to the study of the cytoprotective mechanisms of selenium nanoparticles in the neuroglial networks of the cerebral cortex under conditions of ischemia/reoxygenation. It was shown for the first time that selenium nanoparticles dose-dependently induce the generation of Ca2+ signals selectively in astrocytes obtained from different parts of the brain. The generation of these Ca2+ signals by astrocytes occurs through the release of Ca2+ ions from the endoplasmic reticulum through the IP3 receptor upon activation of the phosphoinositide signaling pathway. An increase in the concentration of cytosolic Ca2+ in astrocytes leads to the opening of connexin Cx43 hemichannels and the release of ATP and lactate into the extracellular medium, which trigger paracrine activation of the astrocytic network through purinergic receptors. Incubation of cerebral cortex cells with selenium nanoparticles suppresses ischemia-induced increase in cytosolic Ca2+ and necrotic cell death. Activation of A2 reactive astrocytes exclusively after ischemia/reoxygenation, a decrease in the expression level of a number of proapoptotic and proinflammatory genes, an increase in lactate release by astrocytes, and suppression of the hyperexcitation of neuronal networks formed the basis of the cytoprotective effect of selenium nanoparticles in our studies.

Determining the effect of aging, recovery time, and post-stroke memantine treatment on delayed thalamic gliosis after cortical infarct.

Secondary injury following cortical stroke includes delayed gliosis and eventual neuronal loss in the thalamus. However, the effects of aging and the potential to ameliorate this gliosis with NMDA receptor (NMDAR) antagonism are not established. We used the permanent distal middle cerebral artery stroke model (pdMCAO) to examine secondary thalamic injury in young and aged mice. At 3 days post-stroke (PSD3), slight microgliosis (IBA-1) and astrogliosis (GFAP) was evident in thalamus, but no infarct. Gliosis increased dramatically through PSD14, at which point degenerating neurons were detected. Flow cytometry demonstrated a significant increase in CD11b+/CD45int microglia (MG) in the ipsilateral thalamus at PSD14. CCR2-RFP reporter mouse further demonstrated that influx of peripheral monocytes contributed to the MG/Mϕ population. Aged mice demonstrated reduced microgliosis and astrogliosis compared with young mice. Interestingly, astrogliosis demonstrated glial scar-like characteristics at two years post-stroke, but not by 6 weeks. Lastly, treatment with memantine (NMDAR antagonist) at 4 and 24 h after stroke significantly reduced gliosis at PSD14. These findings expand our understanding of gliosis in the thalamus following cortical stroke and demonstrate age-dependency of this secondary injury. Additionally, these findings indicate that delayed treatment with memantine (an FDA approved drug) provides significant reduction in thalamic gliosis.

Prior perineural or neonatal treatment with capsaicin does not alter the development of spinal microgliosis induced by peripheral nerve injury.

Peripheral nerve injury is associated with spinal microgliosis which plays a pivotal role in the development of neuropathic pain behavior. Several agents of primary afferent origin causing the microglial reaction have been identified, but the type(s) of primary afferents that release these mediators are still unclear. In this study, specific labeling of C-fiber spinal afferents by lectin histochemistry and selective chemodenervation by capsaicin were applied to identify the type(s) of primary afferents involved in the microglial response. Comparative quantitative morphometric evaluation of the microglial reaction in central projection territories of intact and injured peripheral nerves in the superficial (laminae I and II) and deep (laminae III and IV) spinal dorsal horn revealed a significant, about three-fold increase in microglial density after transection of the sciatic or the saphenous nerve. Prior perineural treatment of these nerves with capsaicin, resulting in a selective defunctionalization of C-fiber afferent fibers failed to affect spinal microgliosis. Similarly, peripheral nerve injury-induced increase in microglial density was unaffected in rats treated neonatally with capsaicin known to result in a near-total loss of C-fiber dorsal root fibers. Perineural treatment with capsaicin per se did not evoke a significant increase in microglial density. These observations indicate that injury-induced spinal microgliosis may be attributed to phenotypic changes in injured myelinated primary afferent neurons, whereas the contribution of C-fiber primary sensory neurons to this neuroimmune response is negligible. Spinal myelinated primary afferents may play a hitherto unrecognized role in regulation of neuroimmune and perisynaptic microenvironments of the spinal dorsal horn.

Hyperleptinemia as a contributing factor for the impairment of glucose intolerance in obesity.

Obesity has emerged as a major risk factor for insulin resistance leading to the development of type 2 diabetes (T2D). The condition is characterized by high circulating levels of the adipose-derived hormone leptin and a state of chronic low-grade inflammation. Pro-inflammatory signaling in the hypothalamus is associated with a decrease of central leptin- and insulin action leading to impaired systemic glucose tolerance. Intriguingly, leptin not only regulates body weight and glucose homeostasis but also acts as a pro-inflammatory cytokine. Here we demonstrate that increasing leptin levels (62,5 µg/kg/d, PEGylated leptin) in mice fed a high-fat diet (HFD) exacerbated body weight gain and aggravated hypothalamic micro- as well as astrogliosis. In contrast, administration of a predetermined dose of a long-acting leptin antagonist (100 µg/kg/d, PESLAN) chosen to block excessive leptin signaling during diet-induced obesity (DIO) showed the opposite effect and significantly improved glucose tolerance as well as decreased the total number of microglia and astrocytes in the hypothalamus of mice fed HFD. These results suggest that high levels of leptin, such as in obesity, worsen HFD-induced micro-and astrogliosis, whereas the partial reduction of hyperleptinemia in DIO mice may have beneficial metabolic effects and improves hypothalamic gliosis.

Liposomal Encapsulated Curcumin Effectively Attenuates Neuroinflammatory and Reactive Astrogliosis Reactions in Glia Cells and Organotypic Brain Slices.

INTRODUCTION: The polyphenolic spice and food coloring ingredient curcumin has beneficial effects in a broad variety of inflammatory diseases. Amongst them, curcumin has been shown to attenuate microglia reaction and prevent from glial scar formation in spinal cord and brain injuries. METHODS: We developed a protocol for the efficient encapsulation of curcumin as a model for anti-inflammatory drugs yielding long-term stable, non-toxic liposomes with favorable physicochemical properties. Subsequently, we evaluate the effects of liposomal curcumin in experimental models for neuroinflammation and reactive astrogliosis. RESULTS: We could show that liposomal curcumin can efficiently reduce the reactivity of human microglia and astrocytes and preserve tissue integrity of murine organotypic cortex slices. DISCUSSION AND PERSPECTIVE: In perspective, we want to administer this curcumin formulation in brain implant coatings to prevent neuroinflammation and glial scar formation as foreign body responses of the brain towards implanted materials.

Ocimum basilicum attenuates ethidium bromide-induced cognitive deficits and pre-frontal cortical neuroinflammation, astrogliosis and mitochondrial dysfunction in rats.

Multiple sclerosis (MS) is a chronic neurodegenerative disorder with clinical symptoms of neuroinflammation and demyelination in the central nervous system. Recently, herbal medicines are clinically effective against MS as the current disease-modifying drugs have limited effectiveness. Hence, the present study evaluated the therapeutic potential of Ocimum basilicum essential oil (OB) in ethidium bromide (EB)-induced cognitive deficits in the male rats. Further, the effect of OB (50, 100 and 200 µL/kg) was evaluated on EB-induced neuroinflammation, astrogliosis and mitochondrial dysfunction in the pre-frontal cortex (PFC) of the animals. The EB was injected through bilateral intracerebroventricular route into hippocampus to induce MS-like manifestations in the rats. OB (100 and 200 µL/kg) and Ursolic acid (UA) significantly reduced the EB-induced cognitive deficits in Morris water maze and Y-maze test paradigms. OB (100 and 200 µL/kg) and UA significantly attenuated the EB-induced neuroinflammation in terms of increase in the levels of pro-inflammatory cytokines (TNF-alpha and IL-6) in the rat PFC. Further, OB (100 and 200 µL/kg) and UA significantly attenuated the EB-induced astrogliosis in terms of increase in the levels of GFAP (Glial fibrillary acidic protein) and Iba-1 (Ionized calcium binding adaptor molecule-1) in the rat PFC. In addition, OB (100 and 200 µL/kg) and UA significantly attenuated the EB-induced decrease in the mitochondrial function, integrity, respiratory control rate and ADP/O in the PFC of the rodents. Moreover, OB (100 and 200 µL/kg) and UA significantly reduced the EB-induced mitochondria-dependent apoptosis in the PFC of the rat. Hence, it can be presumed that OB could be a potential alternative drug candidate in the pharmacotherapy of MS.

Butanol Extract of Tinospora cordifolia Ameliorates Cognitive Deficits Associated with Glutamate-Induced Excitotoxicity: A Mechanistic Study Using Hippocampal Neurons.

Overstimulation of glutamate receptors leads to development of excitotoxicity, which is implicated as final destructive pathway in neurodegenerative diseases. Development of alternative therapeutic strategies effective against glutamate-induced excitotoxicity is much in demand. Herbal drug development is emerging as a major research area for the treatment of various debilitating diseases due to multimodal action and least side effects of herbal products. The current study was aimed to investigate neuroprotective potential of butanol extract of Tinospora cordifolia (B-TCE) against glutamate-induced excitotoxicity using primary hippocampal neurons as in vitro and Wistar strain albino rats as in vivo model systems. Molecular and behavioral parameters were studied to elucidate the underlying mechanism of beneficial effects of B-TCE. B-TCE treatment was also effective in prevention of anxiety, cognition, and motor-coordination deficits induced by glutamate. B-TCE pre-treatment protected the hippocampal neurons from glutamate-induced neurodegeneration and impaired plasticity. At molecular level, B-TCE was observed to attenuate overactivation of glutamate receptors. B-TCE promoted upregulation of ERK and AKT pathways of synaptic plasticity and cell survival in the hippocampus region of brain. This study provides first evidence of neuroprotective potential of B-TCE against glutamate-induced excitotoxicity in hippocampus region and suggests that B-TCE may act as a potential candidate for neuroprotective therapeutic approaches. A single compound 'tinosporicide' was further isolated from B-TCE, which was found to be effective at 800× lower concentration against glutamate-induced neurodegeneration under in vitro conditions.

WBQ5187, a Multitarget Directed Agent, Ameliorates Cognitive Impairment in a Transgenic Mouse Model of Alzheimer's Disease and Modulates Cerebral ß-Amyloid, Gliosis, cAMP Levels, and Neurodegeneration.

Previously, we designed, synthesized, and evaluated a series of quinolone-benzofuran derivatives as multitargeted anti-Alzheimer's disease (anti-AD) compounds, and we discovered that WBQ5187 possesses superior anti-AD bioactivity. In this work, we investigated the pharmacokinetics of this new molecule, as well as its therapeutic efficacy in restoring cognition and neuropathology, in the APP/PS1 mouse model of AD. Pharmacokinetic analyses demonstrated that WBQ5187 possessed rational oral bioavailability, metabolic stability, and excellent blood-brain barrier (BBB) permeability. Pharmacodynamics studies indicated that a 12-week treatment with the lead compound at doses of 40 mg/kg or higher significantly enhanced the learning and memory performance of the APP/PS1 transgenic mice, and the effect was more potent than that of clioquinol (CQ). Furthermore, WBQ5187 notably reduced cerebral ß-amyloid pathology, gliosis, and neuronal cell loss and increased the levels of cAMP in the hippocampus of these mice. The surrogate measures of emesis indicated that WBQ5187 had no effect at its cognitive effective doses. Overall, our results demonstrated that this compound markedly improves cognitive and spatial memory functions in AD mice and represents a promising pharmaceutical agent with potential for the treatment of AD.

Malva sylvestris extract alleviates the astrogliosis and inflammatory stress in LPS-induced depression mice.

Neuro-inflammation is widely regarded as the inflammation occurred in the central nervous system (CNS) tissue, which authentically involved in the pathogenesis such as depression although the underlying mechanism remains to be elucidated. Malva sylvestris (MS), a plant widely used in traditional medicine to mitigate urological, respiratory and oral diseases, exhibits excellent anti-oxidative and anti-inflammatory properties. In the present study, we first used LPS-induced depression-like mice to evaluate the neuro-protective effect of MS extract. We found that, after 7 days' administration of MS extract, the cognitive impairment of LPS-induced depression-like mice was efficiently alleviated, evaluated by behavioral test including the Open field, Morris water maze (MWM), Elevated plus-maze (EPM) and Rota-rod test. Furthermore, we found that MS extract also inhibited the LPS-induced neuron apoptosis and astrogliosis both in the cortex and the CA1 region of hippocampus. Finally, our findings showed that the extract of MS relieved inflammatory stress induced by LPS injury, indicated by the down-regulation of IL-1ß/6 and TNF-α, and up-regulation of IL-4 level both in vitro and in vivo. Collectively, MS extract exhibits neuro-protective activity in vivo, and therefore, it may be widely used for food to relieve the symptoms of neuro-inflammation associated disorders such as depression.

Anti-hyperalgesic effect of (-)-α-bisabolol and (-)-α-bisabolol/ß-Cyclodextrin complex in a chronic inflammatory pain model is associated with reduced reactive gliosis and cytokine modulation.

Chronic pain is a continuous or recurring pain which exceeds the normal course of recovery to an injury or disease. According to the origin of the chronic pain, it can be classified as inflammatory or neuropathic. This study aimed to evaluate the antinociceptive and anti-inflammatory effect of (-)-α-bisabolol (BIS) alone and complexed with ß-cyclodextrin (ßCD) in preclinical models of chronic pain. Chronic pain was induced by Freund's Complete Adjuvant (FCA) or partial lesion of the sciatic nerve (PLSN). Swiss mice were treated with BIS, BIS-ßCD (50 mg/kg, p.o) or vehicle (control) and mechanical hyperalgesia, thermal hyperalgesia, muscle strength and motor coordination were evaluated. In addition, levels of TNF-α and IL-10 and expression of the ionized calcium-binding adapter protein (IBA-1) were assessed in the spinal cord of the mice. The complexation efficiency of BIS in ßCD was evaluated by High-Performance Liquid Chromatography. BIS and BIS-ßCD reduced (p < 0.001) mechanical and thermal hyperalgesia. No alterations were found in force and motor coordination. In addition, BIS and BIS-ßCD inhibited (p < 0.05) TNF-α production in the spinal cord and stimulated (p < 0.05) the release of IL-10 in the spinal cord in PLSN-mice. Further, BIS and BIS-ßCD reduced IBA-1 immunostaining. Therefore, BIS and BIS-ßCD attenuated hyperalgesia, deregulated cytokine release and inhibited IBA-1 expression in the spinal cord in the PLSN model. Moreover, our results show that the complexation of BIS in ßCD reduced the therapeutic dose of BIS. We conclude that BIS is a promising molecule for the treatment of chronic pain.

Pretreatment with Korean red ginseng or dimethyl fumarate attenuates reactive gliosis and confers sustained neuroprotection against cerebral hypoxic-ischemic damage by an Nrf2-dependent mechanism.

The transcriptional factor Nrf2, a master regulator of oxidative stress and inflammation that are tightly linked to the development and progression of cerebral ischemia pathology, plays a vital role in inducing the endogenous neuroprotective process. Here, hypoxic-ischemia (HI) was performed in adult Nrf2 knockout and wildtype mice that were orally pretreated either with standardized Korean red ginseng extract (Ginseng) or dimethyl fumarate (DMF), two candidate Nrf2 inducers, to determine whether the putative protection was through an Nrf2-dependent mechanism involving the attenuation of reactive gliosis. Results show that Nrf2 target cytoprotective genes were distinctly elevated following HI. Pretreatment with Ginseng or DMF elicited robust neuroprotection against the deterioration of acute cerebral ischemia damage in an Nrf2-dependent manner as revealed by the reductions of neurological deficits score, infarct volume and brain edema, as well as enhanced expression levels of Nrf2 target antioxidant proteins and anti-inflammation mediators. In both ischemic striatum and cortex, the dynamic pattern of attenuated reactive gliosis in astrocytes and microglia, including affected astrocytic dysfunction in glutamate metabolism and water homeostasis, correlated well with the Nrf2-dependent neuroprotection by Ginseng or DMF. Furthermore, such neuroprotective benefits extended to the late phase of ischemic brain damage after HI, as evidenced by improvements in neurobehavioral outcomes, infarct volume and brain edema. Overall, pretreatment with Ginseng or DMF identically attenuates reactive gliosis and confers long-lasting neuroprotective efficacy against ischemic brain damage through an Nrf2-dependent mechanism. This study also provides new insight into the profitable contribution of reactive gliosis in the Nrf2-dependent neuroprotection in acute brain injury.

Neuronal preservation and reactive gliosis attenuation following neonatal sciatic nerve axotomy by a fluorinated cannabidiol derivative.

Immature peripheral nervous system damage, such as the transection of a peripheral nerve, results in the extensive degeneration of motoneurons and dorsal root ganglia (DRG) sensory neurons, mostly due to apoptotic events. We have previously shown that cannabidiol (CBD), the most abundant non-psychotropic molecule present in the Cannabis sativa plant, exhibits neuroprotective action when administered daily at a dose of 15 mg/kg. This study shows that use of the fluorinated synthetic version of CBD (4'-fluoro-cannabidiol, HUF-101) significantly improves neuronal survival by 2-fold compared to that achieved with traditional CBD at one-third the dose. Furthermore, we show that HUF-101 administration significantly upregulates anti-apoptotic genes and blocks the expression of pro-apoptotic nuclear factors. Two-day-old Wistar rats were subjected to unilateral sectioning of the sciatic nerve and treated daily with HUF-101 (1, 2.5, 5 mg/kg/day, i.p.) or a vehicle solution for five days. The results were evaluated by Nissl staining, immunohistochemistry, and qRT-PCR. Neuronal counting revealed a 47% rescue of spinal motoneurons and a 79% rescue of DRG neurons (HUF-101, 5 mg/kg). Survival was associated with complete depletion of p53 and a 60-fold elevation in BCL2-like 1 gene expression. Additionally, peroxisome proliferator-activated receptor gamma (PPAR-gamma) gene expression was downregulated by 80%. Neuronal preservation was coupled with a high preservation of synaptic coverage and a reduction in astroglial and microglial reactions that were evaluated in nearby spinal motoneurons present in the ventral horn of the lumbar intumescence. Overall, these data strongly indicate that HUF-101 exerts potent neuroprotective effects that are related to anti-apoptotic protection and the reduction of glial reactivity.

Withania somnifera as a Potential Anxiolytic and Anti-inflammatory Candidate Against Systemic Lipopolysaccharide-Induced Neuroinflammation.

Reactive gliosis, microgliosis, and subsequent secretion of various inflammatory mediators like cytokines, proteases, reactive oxygen, and nitrogen species are the suggested key players associated with systemic inflammation-driven neuroinflammation and cognitive impairments in various neurological disorders. Conventionally, non-steroidal anti-inflammatory drugs are prescribed to suppress inflammation but due to their adverse effects, their usage is not well accepted. Natural products are emerging better therapeutic agents due to their affordability and inherent pleiotropic biological activities. In Ayurveda, Ashwagandha (Withania somnifera) is well known for its immunomodulatory properties. The current study is an extension of our previous report on in vitro model system and was aimed to investigate anti-neuroinflammatory potential of water extract from the Ashwagandha leaves (ASH-WEX) against systemic LPS-induced neuroinflammation and associated behavioral impairments using in vivo rat model system. Oral feeding of ASH-WEX for 8 weeks significantly ameliorated the anxiety-like behavior as evident from Elevated plus maze test. Suppression of reactive gliosis, inflammatory cytokines production like TNF-α, IL-1ß, IL-6, and expression of nitro-oxidative stress enzymes like iNOS, COX2, NOX2 etc were observed in ASH-WEX-treated animals. NFκB, P38, and JNK MAPKs pathways analysis showed their involvement in inflammation suppression which was further confirmed by inhibitor studies. The current study provides first ever preclinical evidence and scientific validation that ASH-WEX exhibits the anti-neuroinflammatory potential against systemic LPS-induced neuroinflammation and ameliorates associated behavioral abnormalities. Aqueous extract from Ashwagandha leaves and its active phytochemicals may prove to be promising candidates to prevent neuroinflammation associated with various neuropathologies.

An anthocyanin-enriched extract from strawberries delays disease onset and extends survival in the hSOD1G93A mouse model of amyotrophic lateral sclerosis.

OBJECTIVE: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting from the death of motor neurons in the brain, brain stem, and spinal cord. Several processes such as oxidative stress, neuroinflammation, and neuronal apoptosis, contribute to disease progression. Anthocyanins are flavonoid compounds derived from fruits and vegetables that possess antioxidant, anti-inflammatory, and anti-apoptotic abilities. Thus, these unique compounds may provide therapeutic benefit for the treatment of ALS. METHODS: We used the G93A mutant human SOD1 (hSOD1G93A) mouse model of ALS to assess the effects of an anthocyanin-enriched extract from strawberries (SAE) on disease onset and progression. Mice were administered SAE orally beginning at 60 days of age until end-stage such that mice received 2 mg/kg/day of the extract's primary anthocyanin constituent. Clinical indices of disease were assessed until mice were sacrificed at end-stage. Histopathological indices of disease progression were also evaluated at 105 days of age. RESULTS: hSOD1G93A mice supplemented with SAE experienced a marked (∼17 day) delay in disease onset and a statistically significant (∼11 day) extension in survival in comparison to their untreated mutant counterparts. Additionally, SAE-treated hSOD1G93A mice displayed significantly preserved grip strength throughout disease progression. Histopathological analysis demonstrated that SAE supplementation significantly reduced astrogliosis in spinal cord, and preserved neuromuscular junctions (NMJs) in gastrocnemius muscle. DISCUSSION: These data are the first to demonstrate that anthocyanins have significant potential as therapeutic agents in a preclinical model of ALS due to their ability to reduce astrogliosis in spinal cord and preserve NMJ integrity and muscle function. Therefore, further study of these compounds is warranted in additional preclinical models of ALS and other neurodegenerative diseases.

Withania somnifera as a potential candidate to ameliorate high fat diet-induced anxiety and neuroinflammation.

BACKGROUND: The epidemic of obesity has reached alarming levels in both developing and developed nations. Excessive calorie intake and sedentary lifestyle due to technological advancements are the main causal factors for overweight and obesity among the human population. Obesity has been associated with a number of co-morbidities such as hypertension, type 2 diabetes mellitus, cardiovascular diseases, and neurodegeneration and dementia. The progression of neurological disorders in obese subjects has been mainly attributed to neuroinflammation. Withania somnifera has been used in numerous Ayurvedic formulations owing to its wide array of health-promoting properties. The current study was designed to test the hypothesis whether dry leaf powder of W. somnifera has anxiolytic and anti-neuroinflammatory potential in diet-induced obesity. METHODS: Young adult female rats were divided into four groups: low fat diet group (LFD) fed with regular chow feed, high fat diet group (HFD) fed with diet containing 30% fat by weight, low fat diet plus extract group (LFDE) fed with regular chow feed supplemented with dry leaf powder of W. somnifera 1 mg/g of body weight (ASH), and high fat diet plus extract group (HFDE) fed with diet containing 30% fat by weight and supplemented with ASH. All the animals were kept on respective feeding regimen for 12 weeks; following which, the animals were tested for their anxiety-like behavior using elevated plus maze test. The animals were sacrificed and used to study various inflammatory markers such as GFAP, Iba1, PPARγ, iNOS, MCP-1, TNFα, IL-1ß, IL-6, and various markers of NF-κB pathway by Western blotting and quantitative real-time PCR. Serum levels of leptin, insulin and pro-inflammatory cytokines were also assayed. RESULTS: ASH treated rats showed less anxiety levels as compared to HFD animals. At molecular level, ASH ameliorated the HFD-induced reactive gliosis and microgliosis and suppressed the expression of inflammatory markers such as PPARγ, iNOS, MCP-1, TNFα, IL-1ß, and IL-6. Further, ASH ameliorated leptin and insulin resistance and prevented HFD-induced apoptosis. CONCLUSIONS: Dry leaf powder of W. somnifera may prove to be a potential therapeutic agent to attenuate neuroinflammation associated with obesity and may prevent its co-morbidities.

Intravitreal injection of docosahexaenoic acid attenuated photoreceptor cell injury in a NaIO3-induced age-related macular degeneration rat model.

In most studies, the major supplement docosahexaenoic acid (DHA) is administered orally or intraperitoneally. In this study, we proposed to assess the safety and efficacy of the intravitreal injection of DHA in an age-related macular degeneration (AMD) rat model. Different concentrations of DHA were injected into the vitreous body. Histopathology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) analysis showed that there was no difference in thickness, observable structure, or apoptosis among the untreated, normal saline, and DHA groups (0.2, 1.0, 5.0 and 10µg). However, GFAP expression was increased in the 10µg group. To investigate whether intravitreal injection of DHA could protect photoreceptors, we developed a NaIO3-induced retinal damage model in adult rats. Decreases in deformation and thickness were observed in the outer nuclear layer (ONL) after NaIO3 administration but were improved with DHA injection. The NaIO3 group showed a substantial reduction in the number of nuclei in ONL, whereas the DHA group showed an increase. Additionally, significant increases in SOD activity and Nrf2 expression were observed after DHA injection; GFAP and NF-κB expression levels were markedly decreased by DHA injection. Moreover, Western blotting showed that Bax, cleaved caspase-3 and CHOP were notably increased in the NaIO3 group but were significantly decreased by DHA injection. Collectively, intravitreal injection of DHA is safe and effective in select doses in a NaIO3-induced AMD rat model. The current results suggest that intravitreal injection of DHA may be a new avenue for the treatment of AMD.

N-butyldeoxynojirimycin delays motor deficits, cerebellar microgliosis, and Purkinje cell loss in a mouse model of mucolipidosis type IV.

Mucolipidosis type IV (MLIV) is a lysosomal storage disease exhibiting progressive intellectual disability, motor impairment, and premature death. There is currently no cure or corrective treatment. The disease results from mutations in the gene encoding mucolipin-1, a transient receptor potential channel believed to play a key role in lysosomal calcium egress. Loss of mucolipin-1 and subsequent defects lead to a host of cellular aberrations, including accumulation of glycosphingolipids (GSLs) in neurons and other cell types, microgliosis and, as reported here, cerebellar Purkinje cell loss. Several studies have demonstrated that N-butyldeoxynojirimycin (NB-DNJ, also known as miglustat), an inhibitor of the enzyme glucosylceramide synthase (GCS), successfully delays the onset of motor deficits, improves longevity, and rescues some of the cerebellar abnormalities (e.g., Purkinje cell death) seen in another lysosomal disease known as Niemann-Pick type C (NPC). Given the similarities in pathology between MLIV and NPC, we examined whether miglustat would be efficacious in ameliorating disease progression in MLIV. Using a full mucolipin-1 knockout mouse (Mcoln1-/-), we found that early miglustat treatment delays the onset and progression of motor deficits, delays cerebellar Purkinje cell loss, and reduces cerebellar microgliosis characteristic of MLIV disease. Quantitative mass spectrometry analyses provided new data on the GSL profiles of murine MLIV brain tissue and showed that miglustat partially restored the wild type profile of white matter enriched lipids. Collectively, our findings indicate that early miglustat treatment delays the progression of clinically relevant pathology in an MLIV mouse model, and therefore supports consideration of miglustat as a therapeutic agent for MLIV disease in humans.