Identification of novel and potential PPARγ stimulators as repurposed drugs for MCAO associated brain degeneration

PPAR agonists for the treatment of neuroinflammatory diseases

Peroxisome proliferator-activated receptors [PPARs; PPARα, PPARβ/δ (also known as PPARδ), and PPARγ] widely recognized for their important role in glucose/lipid homeostasis, have recently received significant attention due to their additional anti-inflammatory and neuroprotective effects. Several newly developed PPAR agonists have shown high selectivity for specific PPAR isoforms in vitro and in vivo, offering the potential to achieve desired therapeutic outcomes while reducing the risk of adverse effects. In this review, we discuss the latest preclinical and clinical studies of the activation of PPARs by synthetic, natural, and isoform-specific (full, partial, and dual) agonists for the treatment of neuroinflammatory diseases, including HIV-associated neurocognitive disorders (HAND), Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), and cerebral ischemia.

Diuretic Potential of Fenchyl Acetate with Its Mechanism of Action: Toxicity Study

Hypertension has become a global threat and is one of the greatest risk factors for chronic kidney disease. Fenchyl acetate is a monoterpene that has been assessed for its various pharmacological activities in the past, but no study has evaluated its diuretic potential and the mechanism involved in the diuretic activity after prolonged administration in rats. Therefore, this study aimed to measure the safety and diuretic profile of fenchyl acetate in rats. For evaluating the acute toxicity, a single dose of 2000 mg/kg was administered as per the OECD guideline no. 425, and the rats were observed for 14 days. After 14 days, blood samples were assessed for biochemical, hematological, and oxidative stress parameters. For the acute diuretic study, fenchyl acetate was given in doses of 100, 200, and 400 mg/kg, and urine samples after 8 h were assessed for sodium, potassium, creatinine, uric acid excretion, and urinary output. A single dose of fenchyl acetate (F.A) was selected for prolonged diuretic activity, and furosemide was taken as the standard drug in a repeated dose administration for 7 days. Rats' urine was assessed for pH, sodium, potassium, creatinine, and uric acid excretion along with urinary volume excretion. Furthermore, blood was withdrawn by cardiac puncture, and selected organs like the heart, liver, kidney, and spleen were analyzed for oxidative stress biomarkers. Using pharmacological antagonists or inhibitors, the involvement of L-NAME, acetylcholine, or prostaglandin in F.A.-induced diuresis was determined. Mitochondrial respiratory chain enzyme complexes were also assessed in the kidney homogenates. The acute toxicity results showed F.A to be safe as its LD50 was greater than 2000 mg/kg and there were no signs of mortality or toxicity. The acute diuretic study showed that F.A resulted in a significant and dose-dependent increase in sodium, potassium, creatinine, and uric acid excretion along with urinary output, and these results were comparable to the standard drug furosemide. Prolonged administration with F.A (400 mg/kg) resulted in a comparable excretion of sodium, potassium, creatinine, uric acid, and urine output with furosemide (15 mg/kg). The oxidative stress parameters revealed that F.A (400 mg/kg) resulted in reducing the formation of free radicals. The results from the mechanism-based studies showed the involvement of NO in inducing diuresis. Furthermore, F.A (400 mg/kg) significantly increased the mitochondrial complexes I, II, III, IV, I + III, and II + III in the kidney homogenates, thus restoring the mitochondrial enzymes and improving the renal function. The current study suggests that F.A is safe with a significant diuretic potential with the involvement of NO in its mechanism of action.

Enhanced cardioprotective activity of ferulic acid-loaded solid lipid nanoparticle in an animal model of myocardial injury

Myocardial infarction results in an increased inflammatory and oxidative stress response in the heart, and reducing inflammation and oxidative stress after MI may offer protective effects to the heart. In the present study, we examined the cardioprotective effects of ferulic acid (FA) and ferulic acid nanostructured solid lipid nanoparticles (FA-SLNs) in an isoproterenol (ISO) induced MI model. Male Sprague Dawley rats were divided into five experimental groups to compare the effects of FA and FA-SLNs. The findings revealed that ISO led to extensive cardiomyopathy, characterized by increased infarction area, edema formation, pressure load, and energy deprivation. Additionally, ISO increased the levels of inflammatory markers (COX-2, NLRP3, and NF-кB) and apoptotic mediators such as p-JNK. However, treatment with FA and FA-SLNs mitigated the severity of the ISO-induced response, and elevated the levels of antioxidant enzymes while downregulating inflammatory pathways, along with upregulation of the mitochondrial bioenergetic factor PPAR-γ. Furthermore, virtual docking analysis of FA with various protein targets supported the in vivo results, confirming drug-protein interactions. Overall, the results demonstrated that FA-SLNs offer a promising strategy for protecting the heart from further injury following MI. This is attributed to the improved drug delivery and therapeutic outcomes compared to FA alone.

A Review on Therapeutic Potential of Natural Phytocompounds for Stroke

Stroke is a serious condition that results from an occlusion of blood vessels that leads to brain damage. Globally, it is the second highest cause of death, and deaths from strokes are higher in older people than in the young. There is a higher rate of cases in urban areas compared to rural due to lifestyle, food, and pollution. There is no effective single medicine for the treatment of stroke due to the multiple causes of strokes. Thrombolytic agents, such as alteplase, are the main treatment for thrombolysis, while multiple types of surgeries, such ascraniotomy, thrombectomy, carotid endarterectomy, and hydrocephalus, can be performed for various forms of stroke. In this review, we discuss some promising phytocompounds, such as flavone C-glycoside (apigenin-8-C-β-D-glucopyranoside), eriodictyol, rosamirinic acid, 6″-O-succinylapigenin, and allicin, that show effectiveness against stroke. Future study paths are given, as well as suggestions for expanding the use of medicinal plants and their formulations for stroke prevention.

Punicalagin Attenuates LPS-Induced Inflammation and ROS Production in Microglia by Inhibiting the MAPK/NF-κB Signaling Pathway and NLRP3 Inflammasome Activation

Purpose

Neurodegenerative diseases are associated with neuroinflammation along with activation of microglia and oxidative stress, but currently lack effective treatments. Punicalagin is a natural bio-sourced product that exhibits anti-inflammatory effects on several chronic diseases; however, the anti-inflammatory and anti-oxidative effects on microglia have not been well examined. This study aimed to investigate the effects of punicalagin on LPS-induced inflammatory responses, NLRP3 inflammasome activation, and the production of ROS using murine microglia BV2 cells.

Methods

BV2 cells were pre-treated with punicalagin following LPS treatment to induce inflammation. The secretion of NO and PGE₂ was analyzed by Griess reagent and ELISA respectively, while the expressions of iNOS, COX-2, STAT3, ERK, JNK, and p38 were analyzed using Western blotting, the production of IL-6 was measured by ELISA, and the activity of NF-κB was detected using promoter reporter assay. To examine whether punicalagin affects NLRP3 inflammasome activation, BV2 cells were stimulated with LPS and then treated with ATP or nigericin. The secretion of IL-1β was measured by ELISA. The expressions of NLRP3 inflammasome-related proteins and phospho IκBα/IκBα were analyzed using Western blotting. The production of intracellular and mitochondrial ROS was analyzed by flow cytometry.

Results

Our results showed that punicalagin attenuated inflammation with reduction of pro-inflammatory mediators and cytokines including iNOS, COX-2, IL-1β, and reduction of IL-6 led to inhibition of STAT3 phosphorylation by LPS-induced BV2 cells. Punicalagin also suppressed the ERK, JNK, and p38 phosphorylation, attenuated NF-κB activity, inhibited the activation of the NLRP3 inflammasome, and reduced the production of intracellular and mitochondrial ROS by LPS-induced BV2 cells.

Conclusion

Our results demonstrated that punicalagin attenuated LPS-induced inflammation through suppressing the expression of iNOS and COX-2, inhibited the activation of MAPK/NF-κB signaling pathway and NLRP3 inflammasome, and reduced the production of ROS in microglia, suggesting that punicalagin might have the potential in treating neurodegenerative diseases.