Protective effect of cyclooxygenase (COX)-inhibitors against drug-induced catatonia and MPTP-induced striatal lesions in rats

Gastroprotective mechanism of Talinum triangulare on ethanol-induced gastric ulcer in Wistar rats via inflammatory, antioxidant, and H+/K+-ATPase inhibition-mediated pathways

The increase in the incidence of gastric ulcer (GU) has posed major threat on public health. This research aimed to evaluate gastroprotective properties of the aqueous leaf extract of Talium triangulare (AETT) in ethanol-induced gastric ulceration. GU was induced via oral administration of single dose of 5 mLkg-1 of 90% ethanol in rats and protection of 200 mgkg-1 bw of AETT and 20 mgkg-1 bw of omeprazole was investigated for 14 d via oral treatment. Influence of AETT on anti-inflammatory, redox assays, ulcer index (UI), and gastric mucosa histological alterations were evaluated. Significant increase in myeloperoxidase (MPO) and tumor necrosis factor-alpha levels compared to untreated group established gastric inflammation in rats induced by ethanol. Gastric ulcerated group exhibited heightened oxidative stress with concurrent decline in activities of antioxidant enzymes. Ethanol exposure to rats resulted in induction of lipid peroxidation, prominently elevating gastric malondialdehyde (MDA) concentration. Nevertheless, treatment with AETT or omeprazole exhibited substantial anti-inflammatory effects within gastric mucosa by attenuating expression of markers associated with inflammation. AETT demonstrated reduction in concentrations of MDA and H2O2, thereby alleviating progression of lipid peroxidation cascades. Also, AETT exhibited mitigating effect on ethanol-induced oxidative harm by enhancing the functionality of protective enzymes and elevating glutathione (GSH) concentration. Overall, AETT exhibited enhancements in activities of cytoprotective antioxidant enzymes, mitigated impact of oxidative stress and inflammation, inhibited lipid peroxidation, and decreased UI score. These beneficial effects could be attributed to phytochemicals present in AETT including 6,10,14-trimethyl-2-pentadecanone and Phytol. Outcome of this study established the traditional herbal claims of AETT.

Case Report of Retarded Catatonia: Always Consider Catatonia as a Differential Diagnosis of Altered Mental Status

BACKGROUND

Catatonia is a rare neuropsychiatric condition; it is estimated that around 10% of patients with mood disorders present signs and symptoms of catatonia. A catatonic syndrome is characterised by mutism, negativism, rigidity, and stupor.

CASE REPORT

We report the case of a 59-year-old patient with a medical history of bipolar disorder who was admitted to the internal medicine service due to a seizure episode. During hospitalisation, the patient presented significant worsening of her clinical condition, showing marked symptoms of stupor and catatonia. Once the neurological and metabolic etiologies of altered mental status had been ruled out, pharmacological treatment with high doses of lorazepam was started. The patient had a complete clinical remission, and her evolution was favourable without any complications. Electroconvulsive therapy was recommended as a definitive treatment.

CONCLUSIONS

The diagnosis of catatonia is a challenge for both hospitalists and psychiatrists due to the clinical presentation of catatonia. In reporting this clinical case, we want to emphasise the importance of taking into account the catatonic syndrome in our differential diagnoses in patients with altered mental status.

Molecular and cellular mechanisms leading to catatonia: an integrative approach from clinical and preclinical evidence

This review aims to describe the clinical spectrum of catatonia, in order to carefully assess the involvement of astrocytes, neurons, oligodendrocytes, and microglia, and articulate the available preclinical and clinical evidence to achieve a translational understanding of the cellular and molecular mechanisms behind this disorder. Catatonia is highly common in psychiatric and acutely ill patients, with prevalence ranging from 7.6% to 38%. It is usually present in different psychiatric conditions such as mood and psychotic disorders; it is also a consequence of folate deficiency, autoimmunity, paraneoplastic disorders, and even autistic spectrum disorders. Few therapeutic options are available due to its complexity and poorly understood physiopathology. We briefly revisit the traditional treatments used in catatonia, such as antipsychotics, electroconvulsive therapy, and benzodiazepines, before assessing novel therapeutics which aim to modulate molecular pathways through different mechanisms, including NMDA antagonism and its allosteric modulation, and anti-inflammatory drugs to modulate microglia reaction and mitigate oxidative stress, such as lithium, vitamin B12, and NMDAr positive allosteric modulators.

Novel therapeutic interventions for combating Parkinson's disease and prospects of Nose-to-Brain drug delivery

Parkinson disease (PD) is a progressive neurodegenerative disorder prevalent mainly in geriatric population. While, L-DOPA remains one of the major choices for the therapeutic management of PD, various motor and non-motor manifestations complicate the management of PD. In the last two decades, exhaustive research has been carried out to explore novel therapeutic approaches for mitigating motor and non-motor symptoms of PD. These approaches majorly include receptor-based, anti-inflammatory, stem-cell and nucleic acid based. The major limitations of existing therapeutic interventions (of commonly oral route) are low efficacy due to low brain bioavailability and associated side effects. Nanotechnology has been exploited and has gained wide attention in the recent years as an approach for enhancement of bioavailability of various small molecule drugs in the brain. To address the challenges associated with PD therapy, nose-to-brain delivery utilizing nanomedicine-based approaches has been found to be encouraging in published evidence. Therefore, the present work summarises the major challenges and limitations with antiparkinsonian drugs, novel therapeutic interventions, and scope of nanomedicine-based nose-to-brain delivery in addressing the current challenges of antiparkinsonian therapy. The manuscript tries to sensitize the researchers for designing brain-targeted nanomedicine loaded with natural/synthetic scaffolds, biosimilars, and nucleic acids that can bypass the first-pass effect for the effective management of PD.

Neuroinflammation in neurological disorders: pharmacotherapeutic targets from bench to bedside

Neuroinflammation is one of the host defensive mechanisms through which the nervous system protects itself from pathogenic and or infectious insults. Moreover, neuroinflammation occurs as one of the most common pathological outcomes in various neurological disorders, makes it the promising target. The present review focuses on elaborating the recent advancement in understanding molecular mechanisms of neuroinflammation and its role in the etiopathogenesis of various neurological disorders, especially Alzheimer's disease (AD), Parkinson's disease (PD), and Epilepsy. Furthermore, the current status of anti-inflammatory agents in neurological diseases has been summarized in light of different preclinical and clinical studies. Finally, possible limitations and future directions for the effective use of anti-inflammatory agents in neurological disorders have been discussed.

Telfairia occidentalis mitigates dextran sodium sulfate-induced ulcerative colitis in rats via suppression of oxidative stress, lipid peroxidation, and inflammation

Ulcerative colitis (UC), a subcategory of inflammatory bowel diseases, affects more than 2 million people globally. This study sought to investigate the curative ability of aqueous leaf extract of Telfairia occidentalis (ATO) on dextran sodium sulfate (DSS)-mediated colitis in rats. UC was induced by 5% of DSS in drinking water, and the curative ability of ATO was assessed at 200 mg/kg by oral administration for 10 days. The effect of ATO was deduced on anti-inflammatory, preclinical features [disease activity index (DAI)], redox assays, and alterations both microscopic and macroscopic of the colonic mucosa. DSS mediated inflammation in colons of rats with a significant increase in nitric oxide, myeloperoxidase, IL-1β, IL-6, and TNF-α levels compared with a control group. Lipid peroxidation was also induced following exposure of rats to DSS. There is a marked decrease in antioxidant enzymes activities in DSS group. However, treatment with ATO markedly inhibited the colonic inflammation by reversing the elevated levels of inflammatory markers. Furthermore, ATO suppressed the lipid peroxidation chain reaction by reducing the level of malondialdehyde and hydrogen peroxide. ATO attenuates DSS-induced oxidative stress by increase the level of GSH and enhancing the activities of the cytoprotective enzymes (catalase, glutathione-S-transferase, and superoxide dismutase). Taken together, ATO reduced DAI score, inhibited inflammation, suppressed lipid peroxidation, attenuated oxidative stress, and enhanced the antioxidant enzymes activities. These therapeutic effects of ATO might be due to its phytochemicals as showed in gas chromatography-mass spectroscopy results. The findings of this study indicate that aqueous leaf extract of T. occidentalis has could be a drug candidate for the treatment of UC. PRACTICAL APPLICATIONS: The study focused on the curative ability of aqueous leaf extract of Telfairia occidentalis on dextran sodium sulfate (DSS) mediated colitis in rats. The extract elicits beneficial effects against colitis via its ability to reduce mucosal inflammation, suppress lipid peroxidation, attenuate oxidative stress, enhance the antioxidant enzymes activities, and reduce both infiltration of inflammatory cells and mucosal damage in colon. This study provides scientific evidence to the therapeutic ability of aqueous leaf extract of T. occidentalis in the treatment of DSS-induced ulcerative colitis and could be a drug candidate for the treatment of inflammatory bowel diseases in humans.

Celecoxib promotes survival and upregulates the expression of neuroprotective marker genes in two different in vitro models of Parkinson's disease

Parkinson's disease (PD) is the second most common age-related neurodegenerative disorder after Alzheimer's disease. Increasing evidence highlights the role of age-related chronic inflammation, oxidative stress and mitochondrial dysfunction in the pathogenesis of PD. A combination of these factors impairs the crosstalk between mitochondria and lysosomes, resulting in compromised cell homeostasis. Apolipoprotein D (APOD), an ancient and highly conserved anti-inflammatory and antioxidant lipocalin, and the transcription factor EB (TFEB), a master regulator of mitophagy, autophagy and lysosomal biogenesis, play key roles in these processes. Both APOD and TFEB have attracted attention as therapeutic targets for PD. The aim of this study was to investigate if the selective cyclooxygenase-2 inhibitor celecoxib (CXB) exerts a direct neuroprotective effect in 6-hydroxydopamine (6-OHDA) and paraquat (PQ) PD models. We found that CXB rescued SH-SY5Y cells challenged by 6-OHDA- and PQ-induced toxicity. Furthermore, treatment with CXB led to a marked and sustained upregulation of APOD and the two microphthalmia transcription factors TFEB and MITF. In sum, this study highlights the clinically approved drug CXB as a promising neuroprotective therapeutic tool in PD research that has the potential to increase the survival rate of dopaminergic neurons that are still alive at the time of diagnosis.

Pharmacological Targeting of Microglial Activation: New Therapeutic Approach

Mounting evidence suggests that neuroinflammation is not just a consequence but a vital contributor to the development and progression of Parkinson’s disease (PD). Microglia in particular, may contribute to the induction and modulation of inflammation in PD. Upon stimulation, microglia convert into activated phenotypes, which exist along a dynamic continuum and bear different immune properties depending on the disease stage and severity. Activated microglia release various factors involved in neuroinflammation, such as cytokines, chemokines, growth factors, reactive oxygen species (ROS), reactive nitrogen species (RNS), and prostaglandins (PGs). Further, activated microglia interact with other cell types (e.g., neurons, astrocytes and mast cells) and are closely associated with α-synuclein (α-syn) pathophysiology and iron homeostasis disturbance. Taken together, microglial activation and microglia-mediated inflammatory responses play essential roles in the pathogenesis of PD and elucidation of the complexity and imbalance of microglial activation may shed light on novel therapeutic approaches for PD.

Celecoxib-induced gastrointestinal, liver and brain lesions in rats, counteraction by BPC 157 or L-arginine, aggravation by L-NAME

AIM

To counteract/reveal celecoxib-induced toxicity and NO system involvement.

METHODS

Celecoxib (1 g/kg b.w. ip) was combined with therapy with stable gastric pentadecapeptide BPC 157 (known to inhibit these lesions, 10 μg/kg, 10 ng/kg, or 1 ng/kg ip) and L-arginine (100 mg/kg ip), as well as NOS blockade [N(G)-nitro-L-arginine methyl ester (L-NAME)] (5 mg/kg ip) given alone and/or combined immediately after celecoxib. Gastrointestinal, liver, and brain lesions and liver enzyme serum values in rats were assessed at 24 h and 48 h thereafter.

RESULTS

This high-dose celecoxib administration, as a result of NO system dysfunction, led to gastric, liver, and brain lesions and increased liver enzyme serum values. The L-NAME-induced aggravation of the lesions was notable for gastric lesions, while in liver and brain lesions the beneficial effect of L-arginine was blunted. L-arginine counteracted gastric, liver and brain lesions. These findings support the NO system mechanism(s), both NO system agonization (L-arginine) and NO system antagonization (L-NAME), that on the whole are behind all of these COX phenomena. An even more complete antagonization was identified with BPC 157 (at both 24 h and 48 h). A beneficial effect was evident on all the increasingly negative effects of celecoxib and L-NAME application and in all the BPC 157 groups (L-arginine + BPC 157; L-NAME + BPC 157; L-NAME + L-arginine + BPC 157). Thus, these findings demonstrated that BPC 157 may equally counteract both COX-2 inhibition (counteracting the noxious effects of celecoxib on all lesions) and additional NOS blockade (equally counteracting the noxious effects of celecoxib + L-NAME).

CONCLUSION

BPC 157 and L-arginine alleviate gastrointestinal, liver and brain lesions, redressing NSAIDs’ post-surgery application and NO system involvement.

Inflammatory response in Parkinson's disease (Review)

Parkinson's disease (PD) is one of the most common age‑related neurodegenerative diseases, which results from a number of environmental and inherited factors. PD is characterized by the slow progressive degeneration of dopaminergic (DA) neurons in the substantia nigra. The nigrostriatal DA neurons are particularly vulnerable to inflammatory attack. Neuroinflammation is an important contributor to the pathogenesis of age‑related neurodegenerative disorders, such as PD, and as such anti‑inflammatory agents are becoming a novel therapeutic focus. This review will discuss the current knowledge regarding inflammation and review the roles of intracellular inflammatory signaling pathways, which are specific inflammatory mediators in PD. Finally, possible therapeutic strategies are proposed, which may downregulate inflammatory processes and inhibit the progression of PD.

Evaluation of the reproductive toxicity of naproxen sodium and meloxicam in male rats

Nonsteroidal anti-inflammatory drugs that are cyclooxygenase (COX) enzyme inhibitors have generally been used in short-term pain management and also to treat inflammation chronically. It is known that COX enzyme and prostaglandins play important roles in the regulation of reproductive functions in females. However, there are relatively few studies for the male reproductive system, and the results of these studies are contradictory. In this study, sperm count and motility, COX-1, COX-2, prostaglandin E1 (PGE1), prostaglandin E2 (PGE2), and prostaglandin F2α (PGF2α) levels in testis tissue, plasma follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone levels, and histopathological examination of testis tissue were evaluated after naproxen sodium and meloxicam administration in male rats. Also, testis superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and glutathione (GSH) levels were measured to investigate the oxidation status. According to our results, sperm count and motility were significantly decreased in treatment groups. Plasma hormone levels did not show any statistical differences between the groups. COX-1, PGE2, and PGF2α levels were significantly decreased, while the decreases in COX-2 and PGE1 levels did not show any significance statistically. Testis SOD, catalase, GPx, and GSH levels were decreased significantly. According to the results of histopathological examination, damage in seminiferous tubules, where spermatogenesis developed, was observed. In conclusion, naproxen sodium and meloxicam decreased the sperm count and motility and also induced the damage of seminiferous tubules as a direct effect without affecting plasma hormone levels in our study. The mechanism of the reproductive toxicity induced by these agents may be based on the inhibition of prostaglandin synthesis and the induction of oxidative stress can be emphasized as a secondary factor.

Neuroprotective potential of atorvastatin and simvastatin (HMG-CoA reductase inhibitors) against 6-hydroxydopamine (6-OHDA) induced Parkinson-like symptoms

Neuro-inflammation and oxidative stress plays a key role in the pathophysiology of Parkinson's disease (PD). Studies demonstrated that neuro-inflammation and associated infiltration of inflammatory cells into central nervous system are inhibited by 3-hydroxy-3-methyl glutaryl co-enzyme A (HMG-CoA) reductase inhibitors. Based on these experimental evidences, the present study has been designed to evaluate the neuroprotective effect of HMG-CoA reductase inhibitors (atorvastatin and simvastatin) against 6-hydroxydopamine (6-OHDA) induced unilateral lesion model of PD. In the present study, the animals were divided into nine groups (n=15 per group). Group I: Naive (without treatment); Group II: Sham (surgery performed, vehicle administered); Group III: Atorvastatin (20mg/kg); Group IV: Simvastatin (30 mg/kg); Group V: Control [Intrastriatal 6-OHDA (20 μg; single unilateral injection)]; Groups VI and VII: 6-OHDA (20 μg)+atorvastatin (10mg/kg and 20mg/kg) respectively; Groups VIII and IX: 6-OHDA (20 μg)+simvastatin (15 mg/kg and 30 mg/kg) respectively. Intrastriatal administration of 6-OHDA (20 μg; 4 μl of 5 μg/μl) significantly caused impairment in body weight, locomotor activity, rota-rod performance, oxidative defense and mitochondrial enzyme complex activity, and increase in the inflammatory cytokine levels (TNF-α and IL-6) as compared to naive animals. Atorvastatin (20mg/kg) and simvastatin (30 mg/kg) drug treatment significantly improved these behavioral and biochemical alterations restored mitochondrial enzyme complex activities and attenuated neuroinflammatory markers in 6-OHDA (20 μg) treated animals as compared to control group. The findings of the present study demonstrate the neuroprotective potential of statins in experimental model of 6-OHDA induced Parkinson like symptoms.

Targeting oxidative stress, mitochondrial dysfunction and neuroinflammatory signaling by selective cyclooxygenase (COX)-2 inhibitors mitigates MPTP-induced neurotoxicity in mice

Several studies have pointed towards the role of oxidative stress, mitochondrial dysfunction and neuroinflammation in Parkinson's disease (PD). The present study was focused on the possible neuroprotective effect of selective cyclooxygenase (COX)-2-inhibitors: valdecoxib and NS-398 in 1-methyl-4-phenyl-1,2,3,6-tertahydropyridine (MPTP)-induced neurotoxicity in mice. MPTP administration in dose of 40 mg/kg, i.p (four injections of 10mg/kg, i.p. at an interval of 1h each) significantly induced the Parkinson-like symptoms in mice as indicated by change in locomotor activity, inability to correct posture (bar test), and oxidative stress (increased levels of lipid peroxidation, nitrite concentration, and depletion of antioxidant enzyme). MPTP administration significantly impaired mitochondrial complex-I activity and redox activity, upregulated the caspase-3 and NF-κB levels as compared to vehicle group. Treatment with valdecoxib (5 or 10 mg/kg, p.o.) or NS-398 (5 or 10mg/kg, p.o.) for 7 days significantly reversed behavioral, biochemical, mitochondrial complex alterations as well as attenuated the induction of proinflammatory mediators in MPTP-treated groups. The findings of the present study substantiate the neuroprotective role of selective COX-2 inhibitors in ameliorating MPTP-induced neurodegeneration in mice and suggest the possible therapeutic potential of these drugs in the management of PD.

Licofelone attenuates MPTP-induced neuronal toxicity: behavioral, biochemical and cellular evidence

Neuroinflammation and oxidative stress play critical role in the pathophysiology of neurodegenerative diseases including Parkinson's disease (PD). Recent reports indicate the beneficial effect of anti-inflammatory drugs in attenuating the progression of PD. Therefore, the present study is aimed to evaluate the possible role of licofelone, a dual COX/LOX-inhibitor against MPTP-induced neurotoxicity in mice. Administration of MPTP (40 mg/kg in divided doses of four injections of 10 mg/kg, i.p. each at 1 h interval) significantly impaired locomotor activity and induced catatonia, oxidative damage (elevated levels of lipid peroxidation, superoxide anion and nitrite, and decreased levels of non-protein thiols) as compared with vehicle-treated animals. Biochemical studies revealed significant alterations in mitochondrial enzyme complex activities (decreased complex-I activity and mitochondrial viability) and increased levels of caspase-3 and NF-κB/p65 as compared to vehicle treated group. Licofelone (2.5, 5 or 10 mg/kg/day, p.o.) treatment for 7 days significantly improved locomotor activity, attenuated the severity of catatonia, oxidative damage and restored mitochondrial enzyme complex activity as compared to MPTP-treated group. Licofelone treatment also attenuated the expression of apoptotic factor (caspase-3) and transcription factor (NF-κB/p65) as compared to MPTP-treated group. The findings of the present study suggest that licofelone (dual inhibitor of COX and LOX) represents a new class of anti-inflammatory agent which may provide a novel therapeutic alternative for the treatment and management of PD.

Non-Steroidal Anti-Inflammatory Drugs in Alzheimer's Disease and Parkinson's Disease: Reconsidering the Role of Neuroinflammation

Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common neurodegenerative diseases with age as the greatest risk factor. As the general population experiences extended life span, preparation for the prevention and treatment of these and other age-associated neurological diseases are warranted. Since epidemiological studies suggested that non-steroidal anti-inflammatory drug (NSAID) use decreased risk for AD and PD, increasing attention has been devoted to understanding the costs and benefits of the innate neuroinflammatory response to functional recovery following pathology onset. This review will provide a general overview on the role of neuroinflammation in these neurodegenerative diseases and an update on NSAID treatment in recent experimental animal models, epidemiological analyses, and clinical trials.