Gene Therapy for Chronic Traumatic Brain Injury: Challenges in Resolving Long-term Consequences of Brain Damage.

The gene therapy is alluring not only for CNS disorders but also for other pathological conditions. Gene therapy employs the insertion of a healthy gene into the identified genome to replace or replenish genes responsible for pathological disorder or damage due to trauma. The last decade has seen a drastic change in the understanding of vital aspects of gene therapy. Despite the complexity of traumatic brain injury (TBI), the advent of gene therapy in various neurodegenerative disorders has reinforced the ongoing efforts of alleviating TBI-related outcomes with gene therapy. The review highlights the genes modulated in response to TBI and evaluates their impact on the severity and duration of the injury. We have reviewed strategies that pinpointed the most relevant gene targets to restrict debilitating events of brain trauma and utilize vector of choice to deliver the gene of interest at the appropriate site. We have made an attempt to summarize the long-term neurobehavioral consequences of TBI due to numerous pathometabolic perturbations associated with a plethora of genes. Herein, we shed light on the basic pathological mechanisms of brain injury, genetic polymorphism in individuals susceptible to severe outcomes, modulation of gene expression due to TBI, and identification of genes for their possible use in gene therapy. The review also provides insights on the use of vectors and challenges in translations of this gene therapy to clinical practices.

Neuroprotective effects of combined trimetazidine and progesterone on cerebral reperfusion injury.

Cerebral ischemia-reperfusion injury induces multi-dimensional damage to neuronal cells through exacerbation of critical protective mechanisms. Targeting more than one mechanism simultaneously namely, inflammatory responses and metabolic energy homeostasis could provide additional benefits to restrict or manage cerebral injury. Being proven neuroprotective agents both, progesterone (PG) and trimetazidine (TMZ) has the potential to add on the individual therapeutic outcomes. We hypothesized the simultaneous administration of PG and TMZ could complement each other to synergize, or at least enhance neuroprotection in reperfusion injury. We investigated the combination of PG and TMZ on middle cerebral artery occlusion (MCAO) induced cerebral reperfusion injury in rats. Molecular docking on targets of energy homeostasis and apoptosis assessed the initial viability of PG and TMZ for neuroprotection. Animal experimentation with MCA induced ischemia-reperfusion (I/R) injury in rats was performed on five randomized groups. Sham operated control group received vehicle (saline) while the other four I-R groups were pre-treated with vehicle (saline), PG (8 â€‹mg/kg), TMZ treated (25 â€‹mg/kg), and PG â€‹+ â€‹TMZ (8 and 25 â€‹mg/kg) for 7 days by intraperitoneal route. Neurological deficit, infarct volume, and oxidative stress were evaluated to assess the extent of injury in rats. Inflammatory reactivity and apoptotic activity were determined with alterations in myeloperoxidase (MPO) activity, blood-brain barrier (BBB) permeability, and DNA fragments. Reperfusion injury inflicted cerebral infarct, neurological deficit, and shattered BBB integrity. The combination treatment of PG and TMZ restricted cellular damage indicated by significant (p â€‹< â€‹0.05) decrease in infarct volume and improvement in free radical scavenging ability (SOD activity and GSH level). MPO activity and LPO decreased which contributed in improved BBB integrity in treated rats. We speculate that inhibition of inflammatory and optimum energy utilization would critically contribute to observed neuroprotection with combined PG and TMZ treatment. Further exploration of this neuroprotective approach for post-recovery cognitive improvement is worth investigating.

Combination therapy for cerebral ischemia: do progesterone and noscapine provide better neuroprotection than either alone in the treatment?

Ischemic stroke presents multifaceted pathological outcomes with overlapping mechanisms of cerebral injury. High mortality and disability with stroke warrant a novel multi-targeted therapeutic approach. The neuroprotection with progesterone (PG) and noscapine (NOS) on cerebral ischemia-reperfusion (I-R) injury was demonstrated individually, but the outcome of combination treatment to alleviate cerebral damage is still unexplored. Randomly divided groups of rats (n = 6) were Sham-operated, I-R, PG (8 mg/kg), NOS (10 mg/kg), and PG + NOS (8 mg/kg + 10 mg/kg). The rats were exposed to bilateral common carotid artery occlusion, except Sham-operated, to investigate the therapeutic outcome of PG and NOS alone and in combination on I-R injury. Besides the alterations in cognitive and motor abilities, we estimated infarct area, oxidative stress, blood-brain barrier (BBB) permeability, and histology after treatment. Pharmacokinetic parameters like Cmax, Tmax, half-life, and AUC0-t were estimated in biological samples to substantiate the therapeutic outcomes of the combination treatment. We report PG and NOS prevent loss of motor ability and improve spatial memory after cerebral I-R injury. Combination treatment significantly reduced inflammation and restricted infarction; it attenuated oxidative stress and BBB damage and improved grip strength. Histopathological analysis demonstrated a significant reduction in leukocyte infiltration with the most profound effect in the combination group. Simultaneous analysis of PG and NOS in plasma revealed enhanced peak drug concentration, improved AUC, and prolonged half-life; the drug levels in the brain have increased significantly for both. We conclude that PG and NOS have beneficial effects against brain damage and the co-administration further reinforced neuroprotection in the cerebral ischemia-reperfusion injury.

Sports-Related Brain Injury and Neurodegeneration in Athletes.

Sports deserve a special place in human life to impart healthy and refreshing wellbeing. However, sports activities, especially contact sports, renders athlete vulnerable to brain injuries. Athletes participating in a contact sport like boxing, rugby, American football, wrestling, and basketball are exposed to traumatic brain injuries (TBI) or concussions. The acute and chronic nature of these heterogeneous injuries provides a spectrum of dysfunctions that alters the neuronal, musculoskeletal, and behavioral responses of an athlete. Many sports-related brain injuries go unreported, but these head impacts trigger neurometabolic disruptions that contribute to long-term neuronal impairment. The pathophysiology of post-concussion and its underlying mechanisms are undergoing intense research. It also shed light on chronic disorders like Parkinson's disease, Alzheimer's disease, and dementia. In this review, we examined post-concussion neurobehavioral changes, tools for early detection of signs, and their impact on the athlete. Further, we discussed the role of nutritional supplements in ameliorating neuropsychiatric diseases in athletes.

Preferential cyclooxygenase inhibition by Jasminum sambac: A possible relationship with potent anti-arthritic activity.

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Aging of Brain Related with Mitochondrial Dysfunctions.

Advancing age presents a major challenge for the elderly population in terms of quality of life. The risk of cognitive impairment, motor in-coordination, and behavioral inconsistency due to neuronal damage is relatively higher in aging individuals of society. The brain, through its structural and functional integrity, regulates vital physiological events; however, the susceptibility of the brain to aging-related disturbances signals the onset of neurodegenerative diseases. Mitochondrial dysfunctions impair bioenergetic mechanism, synaptic plasticity, and calcium homeostasis in the brain, thus sufficiently implying mitochondria as a prime causal factor in accelerating aging-related neurodegeneration. We have reviewed the fundamental functions of mitochondria in a healthy brain and aimed to address the key issues in aging-related diseases by asking: 1) What goes wrong with mitochondria in the aging brain? 2) What are the implications of mitochondrial damage on motor functions and psychiatric symptoms? 3) How environmental chemicals and metabolic morbidities affect mitochondrial functions? Further, we share insights on opportunities and pitfalls in drug discovery approaches targeting mitochondria to slow down the progression of aging and related neurodegenerative diseases.

Noscapine alleviates cerebral damage in ischemia-reperfusion injury in rats.

With high unmet medical needs, stroke remains an intensely focused research area. Although noscapine is a neuroprotective agent, its mechanism of action in ischemic-reperfusion (I-R) injury is yet to be ascertained. We investigated the effect of noscapine on the molecular mechanisms of cell damage using yeast, and its neuroprotection on cerebral I-R injury in rats. Yeast, both wild-type and Δtrx2 strains, was evaluated for cell growth and viability, and oxidative stress to assess the noscapine effect at 8, 10, 12, and 20 µg/ml concentrations. The neuroprotective activity of noscapine (5 and 10 mg/kg; po for 8 days) was investigated in rats using middle cerebral artery occlusion-induced I-R injury. Infarct volume, neurological deficit, oxidative stress, myeloperoxidase activity, and histological alterations were determined in I-R rats. In vitro yeast assays exhibited significant antioxidant activity and enhanced cell tolerance against oxidative stress after noscapine treatment. Similarly, noscapine pretreatment significantly reduced infarct volume and edema in the brain. The neurological deficit was decreased and oxidative stress biomarkers, superoxide dismutase activity and glutathione levels, were significantly increased while lipid peroxidation showed significant decrease in comparison to vehicle-treated I-R rats. Myeloperoxidase activity, an indicator of inflammation, was also reduced significantly in treated rats; histological changes were attenuated with noscapine. The study demonstrates the protective effect of noscapine in yeast and I-R rats by improving cell viability and attenuating neuronal damage, respectively. This protective activity of noscapine could be attributed to potent free radical scavenging and inhibition of inflammation in cerebral ischemia-reperfusion injury.

Development of novel topical drug delivery system containing cisplatin and imiquimod for dual therapy in cutaneous epithelial malignancy.

CONTEXT: Strategy of dual therapy has been proposed to minimize the amount of each drug and to achieve the synergistic effect for cancer therapies. OBJECTIVE: The aim of this study was to develop an effective drug delivery system for the simultaneous topical delivery of two anti-tumor agents, cisplatin and imiquimod. MATERIAL AND METHODS: The preformulation studies were carried out in terms of tests for identification, solubility profile, determination of partition coefficient and simultaneous estimation of both drugs by UV-Visible spectrophotometer and High Performance Liquid Chromatography (HPLC). Drug-drug and drug-excipients interactions were examined by thin layer chromatography, infrared spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Provesicular drug delivery system (protransfersome gel formulation) have been prepared and characterized by in vitro and in vivo parameters. RESULTS: The mean size, poly dispersity index (PDI) and zeta potential of transfersomal vesicles formed by protransfersome hydration were 429.5 nm, 0.631 and -68.1 Mv, respectively. The prepared formulation showed toxicity on cutaneous squamous cell carcinoma cell line (A-431) at 200 µg (cisplatin) and 1 mg (imiquimod) concentration of drug in combination against control. The cisplatin- and imiquimod-loaded provesicular dual-drug delivery system achieved an optimal antitumor effect, increase in lifespan, antiviral, and toxicity reduction, revealing the advantage of site specific drug delivery and the modified combination therapy. DISCUSSION: Cisplatin delivery through protransfersome gel in combination with imiquimod may potentiate the activity against solid tumors of epidermal origin. CONCLUSION: Data revealed that combination therapy considerably enhances antitumor efficacy of the drug for skin-cited malignancies.

Omeprazole improves the anti-obesity and antidiabetic effects of exendin-4 in db/db mice (-4 db/db)*.

BACKGROUND: In addition to its glucoregulatory actions, exendin-4, a stable glucagon-like peptide-1 receptor agonist, exhibits protective effects in the pancreas and anti-obesity effects. Suitable combination treatment with other anti-obesity or pancreas protective agents would be an effective approach to optimize these additional effects. In the present study, we investigated the effects of the addition of omeprazole, a proton pump inhibitor, to exendin-4 in db/db mice, an experimental model of obesity and type 2 diabetes. METHODS: The effects repeated dose treatment for 14 days with exendin-4 (8 µg/kg, s.c.) and omeprazole (30 mg/kg, s.c.) on glycemic control, food intake, and body weight were determined in obese and hyperglycemic db/db mice. The effects of these treatments on plasma gastrin, ghrelin, and leptin levels were determined, along with effects on nausea-like symptoms. The pancreatic effects of the repeated dose treatment were assessed by measuring %HbA1c in the circulation as well as pancreatic insulin and glucagon content and glucokinase activity. RESULTS: Combination treatment resulted in significant decreases in plasma leptin and ghrelin levels after repeated dosing. Omeprazole improved the anorectic and body weight-lowering effects and reversed the inhibitory effect of exendin-4 on gastrin levels after repeated dose treatment. The 14-day combination treatment significantly reduced glucose excursion and improved insulin levels, with a concomitant decrease in %HbA1c levels. It also improved glucokinase activity and pancreatic insulin content, with a significant decrease in glucagon content. CONCLUSIONS: Combined treatment with omeprazole with exendin-4 reduces food intake and body weight gain, most likely through changes in plasma ghrelin and leptin levels, and improves pancreatic insulin and glucagon content by improving glucokinase activity.

Exendin-4 reduces glycemia by increasing liver glucokinase activity: an insulin independent effect.

Exendin-4 is a stable peptide agonist of GLP-1 receptor that exhibits insulinotropic actions. Some in vivo studies indicated insulin-independent glucoregulatory actions of exendin-4. That finding prompted us to evaluate effects of exendin-4 on liver glucose metabolism. Acute and chronic treatment of exendin-4 resulted in increased hepatic glucokinase activity in db/db mice but not in lean C57 mice. The stimulatory effect of exendin-4 on glucokinase activity was abrogated by exendin 9-39, a GLP-1 antagonist. Exposure of hepatocytes isolated from db/db mice to exendin-4 elicited a rapid increase in cAMP, which was synergized by IBMX, an inhibitor of cAMP degradation. The GLP-1 antagonist, exendin 9-39, has abolished the cAMP generating effects of exendin-4 as well. Furthermore, chronic treatment of exendin-4 in streptozotocin-treated C57 mice resulted in restoration of hepatic glycogen, an indicator of improved glucose metabolism, without apparent changes in serum insulin levels. In conclusion, exendin-4 increased glucokinase enzyme protein and activity in liver via a mechanism parallel to and independent of insulin. Exendin-4-induced increase in hepatic glucokinase activity is more pronounced in the presence of hepatic insulin resistance. This beneficial effect of exendin-4 on liver glucokinase activity may be mediated by GLP-1 receptor.

Exendin-4 ameliorates diabetic symptoms through activation of glucokinase.

BACKGROUND: Glucagon-like peptide-1 (GLP-1) and its stable analogue exendin-4 maintain glucose homeostasis by modulating insulin secretion from pancreatic ß-cells and controlling hepatic glucose output. Glucokinase (GK), by catalysing the first step in glycolysis, plays an important role in glucose-stimulated insulin secretion and hepatic glucose metabolism. In the present study, we investigated the effects of exendin-4 on GK in high fat-fed and alloxan-treated diabetic mice. METHODS: The effects of alloxan (5, 10 and 20 µmol/L) on insulin release from isolated murine islets, as well as glycogen synthesis by isolated murine hepatocytes, were assessed. The effects of exendin-4 (10 nmol/kg, twice daily for 4 weeks) were assessed in high fat-fed, alloxan (50 mg/kg, i.v.)-treated C57 mice. Glucokinase activity was assessed in the same model. RESULTS: Pretreatment with exendin-4 attenuated alloxan-induced decreases in insulin release and glycogen synthesis in islets and hepatocytes. The alloxan-induced decrease in the GK activity in islets and hepatocytes was also ameliorated by exendin-4 treatment. Pretreatment with the GLP-1 receptor antagonist exendin-9 (100 nmol/L) blocked the effects of exendin-4 on the liver and pancreas. Treatment of high-fat fed, alloxan-treated diabetic mice with exendin-4 (10 nmol/L, i.p.) reduced the severity of diabetic symptoms. Specifically, exendin-4 treatment reduced serum glucose by 50% and %HbA1c by 24% compared with control and significantly decreased HOMA-IR by 39% and increased HOMA-ß by 150%. In addition, exendin-4 treatment significantly reduced body weight by 6.8% and serum triglycerides by 35%. CONCLUSIONS: The results indicate that glucose-stimulated insulin release and glycogen synthesis are decreased by alloxan due to reduced GK activity. These findings provide further insight into the mechanism by which exendin-4 regulates glucose homeostasis.

Inhibition of 11ß-hydroxysteroid dehydrogenase 1 by carbenoxolone affects glucose homeostasis and obesity in db/db mice.

1. One of the major causes of metabolic syndrome is elevated 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) in the liver and adipose tissue. High 11ß-HSD1 expression contributes significantly to the diabetic phenotype in db/db mice. The purpose of the present study was to test the effect of the pharmacological inhibition of 11ß-HSD1 inhibition by carbenoxolone in db/db mice, a genetic model of diabetes. 2. Inhibition of 11ß-HSD1 by carbenoxolone was evaluated in liver homogenates obtained from untreated mice. At 0.4, 0.8, 1.6 and 3.2 µmol/L, carbenoxolone reduced the conversion of cortisone to cortisol by 21%, 48%, 82% and 95%, respectively. 3. In another series of experiments in which female db/db mice were dosed orally with carbenoxolone (10, 25 and 50 mg/kg, twice daily) for 10 days, dose-dependent decreases were observed in 11ß-HSD1 activity in the brain, adipose and liver. In the case of 10 mg/kg carbenoxolone, the effects were not significant. In addition, the bodyweight of female db/db mice was reduced by 10% and 13% following treatment with 10 and 50 mg/kg carbenoxolone, respectively. Carbenoxolone treatment dose-dependently improved fat mass, energy expenditure, the serum lipid profile, serum leptin and insulin and glucose tolerance. Furthermore, 50 mg/kg carbenoxolone reduced both phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) activity in the liver by 75% and 52%, respectively. These decreases were associated with increased glucokinase protein expression and activity in the liver. 4. Carbenoxolone inhibition of 11ß-HSD1 in the liver, adipose and brain significantly improves the symptoms of metabolic syndrome in db/db mice. These improvements can be attributed to increased energy expenditure, decreased activity of the gluconeogenic enzymes PEPCK and G6Pase in the liver and improved glucokinase function in the liver and pancreas.

Inhibition of microsomal triglyceride transfer protein improves insulin sensitivity and reduces atherogenic risk in Zucker fatty rats.

1. Insulin-resistant states are commonly associated with a significantly higher risk of atherosclerosis. Insulin resistance has also been correlated with enhanced very low-density lipoprotein (VLDL) production, which is exacerbated by increased intestinal lipid synthesis and insulin-stimulated de novo lipogenesis. Microsomal triglyceride transfer protein (MTP) catalyses the critical step in the synthesis and secretion of VLDL and chylomicrons. The purpose of the present study was to test the hypothesis that chronic inhibition of MTP with a small molecule inhibitor would improve insulin sensitivity and reduce atherogenic risk in a genetic model of diabetic dyslipidaemia. 2. The in vivo activity of BMS-201038, a potent inhibitor of MTP, was evaluated in a model of hypertriglyceridemia induced by Triton WR1339 and corn oil in Zucker fatty rats. Triglyceride secretion rate was significantly reduced by a single dose of BMS-201038 by 35% at 0.3 mg/kg and 47% at 1 mg/kg, respectively. 3. Another group of Zucker fatty rats was dosed orally with BMS-201038 (0.3 and 1 mg/kg) for 14 days. Serum levels of triglycerides were reduced by 71% and 87%, non-esterified free fatty acids were reduced by 33% and 40%, and low-density lipoproteins by 26% and 29%, by 0.3 mg/kg and 1 mg/kg dose of BMS-201038, respectively. These serum lipid changes were accompanied by significant improvements in glucose tolerance and insulin sensitivity. In addition, lipid peroxidation in liver was reduced by 59% and 61%, and superoxide dismutase activity was increased by 11% and 45% by 0.3 mg/kg and 1 mg/kg dose of BMS-201038, respectively. Similar beneficial changes were found in aorta as well. 4. The present study provides evidence that inhibition of MTP with a small molecule inhibitor significantly improves dyslipidaemia associated with insulin resistance and reduces the atherosclerotic risk.

Anti-oxidant activity mediated neuroprotective potential of trimetazidine on focal cerebral ischaemia-reperfusion injury in rats.

1. The present study was designed to investigate the neuroprotective effect of trimetazidine (TMZ) following focal cerebral ischaemia-reperfusion (I/R) injury in rat forebrain. 2. Cerebral I/R injury was induced in rats by middle cerebral artery occlusion (MCAO) for 2 h, followed by reperfusion for 22 h. Trimetazidine (5 and 25 mg/kg, i.p.) was administered 1 h after induction of MCAO. The effects of TMZ were investigated by measuring neurological deficit, volume of infarct and brain swelling after 22 h reperfusion. Oxidative stress and inflammatory reactivity were assessed by estimating anti-oxidant markers and myeloperoxidase (MPO) activity in brain homogenates. Rectal temperature was measured during the study. The effects of TMZ on blood-brain barrier (BBB) permeability and apoptosis were also investigated in rat brain. Apoptosis was observed by DNA fragmentation studies using agarose gel electrophoresis. 3. Treatment with TMZ significantly (P < 0.01) reduced infarct volume and brain swelling. Superoxide dismutase (SOD) activity was reduced in ipsilateral hemispheres of vehicle (saline)-treated reperfused (RI) animals. Treatment with TMZ significantly restored SOD activity (P < 0.01) and glutathione levels (P < 0.05) after reperfusion compared with RI animals. Lipid peroxidation, MPO activity, BBB permeability and rectal temperature were all significantly (P < 0.01, P < 0.05 and P < 0.001, respectively) reduced in TMZ-treated animals compared with RI animals. 4. These results suggest that TMZ protects the brain against cerebral I/R injury and that this neuroprotective activity could be mediated by its anti-oxidant properties. The reduction in rectal temperature by TMZ treatment may be responsible for maintaining the delicate energy balance during I/R injury in rat brain and could have contributed to the neuroprotective activity of TMZ.

Gender specific effect of progesterone on myocardial ischemia/reperfusion injury in rats.

The study was designed to investigate the effect of progesterone and its gender based variation on myocardial ischemia/reperfusion (I/R) injury in rats. Adult Sprague Dawley rats were divided into vehicle treated reperfusion injury group male (I/R-M), female (I/R-F), ovariectomised (I/R-OVR) and progesterone treatment (I/R-M+PG, I/R-F+PG, I/R-OVR+PG) groups, respectively. I/R injury was produced by occluding the left descending coronary artery (LCA) for 1 h and followed by re-opening for 1 h. Progesterone (2 mg kg(-1) i.p.) was administered 30 min after induction of ischemia. Hemodynamic parameters (+/-dp/dt, MAP), heart rate, ST-segment elevation and occurrence of ventricular tachycardia (VT) were measured during the I/R period. The myocardial infarct area, oxidative stress markers, activities of myeloperoxidase (MPO) and creatine kinase (CK) were determined after the experiment along with the assessment of the effect on apoptotic activity by using DNA fragmentation analysis. Histological observations were carried out on heart tissue. Treatment with progesterone significantly (P<0.05) reduced infarct area, lipid peroxidation (LPO) level and activity of MPO in females (I/R-F+PG) as compared to ischemic females (I/R-F). Progesterone significantly (P<0.001, P<0.05) inhibited serum CK activity and incidences of VT in female rats. Superoxide dismutase (SOD) activity, reduced glutathione (GSH) levels were significantly elevated (P<0.05) in I/R-F+PG group. Internucleosomal DNA fragmentation was less in I/R-F+PG group when compared to I/R-F group. The ischemic male and ovariectomised (I/R-M and I/R-OVR) counterparts did not show any significant change after progesterone treatment. In conclusion, the cardioprotective effect of progesterone on myocardial I/R injury induced damage is based on gender of the animal. The protective effect could be mediated by attenuation of inflammation and its possible interaction with endogenous estrogen.