Levocabastine ameliorates cyclophosphamide-induced cardiotoxicity in Swiss albino mice: Targeting TLR4/NF-κB/NLRP3 signaling pathway.

Cyclophosphamide (CP), although a potent anti-cancer drug, causes cardiotoxicity as a side effect that limits its use. Hence, a specific medicine that can lower cardiotoxicity and be utilised as an adjuvant in cancer treatment is very much needed. In this light, we intended to assess the protective potential of levocabastine (LEV) on CP-induced cardiotoxicity in Swiss albino mice. Mice were administered LEV (50 and 100 µg/kg, i.p.) daily for 14 days and CP at 200 mg/kg, intraperitoneally once on the 7th day. On the 15th day, mice were weighed, blood withdrawn then sacrificed and hearts were removed to estimate various biochemical and histopathological parameters. CP 200 mg/kg significantly increased cardiac troponin T, LDH, CK-MB, interleukin-1ß, IL-6, TNF-α, TBARS, nitrite, and decreased CAT, GSH, and SOD levels, thus, manifested cardiac damage, inflammation, oxidative stress, and nitrative stress, cumulatively causing cardiotoxicity. CP also elevated the expression of various markers including cleaved caspase-3, NF-κB, TLR4, NLRP3, and fibrotic lesions in cardiac tissues, whereas decreased hematological parameters (RBCs, platelets, and Hb) to confirm cardiotoxicity. LEV and fenofibrate (FF) treatment reversed these changes towards normal and showed a significant protective effect against CP. The results showed the protective role of LEV in restoring CP-induced cardiotoxicity in terms of inflammation, apoptosis, oxidative stress, cardiac injury and histopathological damage. Thus, levocabastine can be used as an adjuvant to cyclophosphamide in cancer treatment but a thorough study with various animal cancer models is further needed to establish the fact.

Effectiveness of estrogen and its derivatives over dexamethasone in the treatment of COVID-19.

Coronavirus disease (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus and dexamethasone is a glucocorticoid widely used for its treatment. Dexamethasone is not used in non-severe cases due to its immunosuppressant action. So, considering this, Estrogen and Estetrol were tested for the treatment of COVID-19 as they all possess a common steroid ring and dislike dexamethasone, they are immunoenhancer. Virtual screening of test ligands was performed through molecular docking, MM-GBSA, simulations, in silico ADMET and drug-likeness prediction to identify their potential to inhibit the effects of SARS-CoV-2. Results showed that test ligands possess drug-like properties and they are safe as drug candidates. The protein-ligand interaction study revealed that they bind with the amino acid residues at the active site of the target proteins and the test ligands possess better binding potential than Dexamethasone. With protein Mpro, Estetrol and Estrogen showed docking score of -7.240 and -5.491 kcal/mol, and with protein ACE2, Estetrol and Estrogen showed docking score of -5.269 and -4.732 kcal/mol, respectively. Further, MD Simulation was carried out and most of the interactions of molecular docking are preserved during simulation. The prominent interactions that our test ligands showed during MD Simulation are similar to drugs that possess in vitro anticovid activity as shown in recent studies. Hence, our test ligands possessed potential for anticovid activity and they should be further tested through in vitro and in vivo studies for their activity against COVID-19.Communicated by Ramaswamy H. Sarma.

Synthesis and HDAC1 inhibitory activity of a novel series of coumarin-based amide derivatives for treatment of cancer.

Background: Histone deacetylases (HDACs) play a vital role in the epigenetic regulation of transcription and expression. HDAC1 overexpression is seen in many cancers. Methodology: The authors synthesized and evaluated 27 novel coumarin-based amide derivatives for HDAC1 inhibitory activity. The compounds were screened at the US National Cancer Institute, and 5k and 5u were selected for five-dose assays. Compound 5k showed GI50 values of 0.294 and 0.264 µM against MOLT-4 and LOX-IMVI, respectively; whereas 5u had GI50 values of 0.189 and 0.263 µM, respectively. Both derivatives showed better activity than entinostat and suberoylanilide hydroxamic acid. Compound 5k exhibited an IC50 value of 1.00 µM on ACHN cells. Conclusion: Coumarin derivatives exhibited promising HDAC1 inhibitory potential and warrant future development as anticancer agents.

A Review on the Synthesis and Anticancer Potentials of Imidazothiazole Derivatives.

Cancer is one of the severe diseases in which abnormal cells divide and proliferate in an uncontrolled manner without any regulation. Globally cancer is among the leading causes of death; according to a recent report of by the WHO, around 10 million people died in 2018 due to cancer. It has also been reported that by 2040, approximately 30 million new cases will be reported every year. The increase in the incidences of cancer is taking a toll on the health care system worldwide. Considerable scientific literature is available on anticancer agents but newer therapeutic strategies are still required in this field to address novel approaches to drug design and discovery to counter this problem. Imidazothiazole represents a privileged scaffold in medicinal chemistry and provides the medicinal chemist the possibility to modulate the physiochemical properties of the lead compound. In recent times, imidazothiazole scaffold is broadly explored for its anticancer activity, which acts through various mechanisms such as EGFR, B-RAF, DHFR kinase inhibition and tubulin polymerization inhibition and other molecular mechanisms of action. Due to their feasible synthetic accessibility and promising pharmacological profile, it has attracted various medicinal chemists to explore and develop imidazothiazole derivatives as potent and safe anticancer agents. In the present article, we have reviewed various potent imidazothiazole scaffold-based derivatives reported as anticancer agents, their synthetic strategies, Structure Activity Relationship (SAR), mechanism of action, and molecular docking along with their future perspective. This review will be very useful for medicinal chemists for drug design and development of imidazothiazole-based potent antiproliferative agents.

Role of NLRP3 Inflammasome and Its Inhibitors as Emerging Therapeutic Drug Candidate for Alzheimer's Disease: a Review of Mechanism of Activation, Regulation, and Inhibition.

Alzheimer's disease (AD) is one of the most prevalent neurodegenerative disorders. The etiology and pathology of AD are complicated, variable, and yet to be completely discovered. However, the involvement of inflammasomes, particularly the NLRP3 inflammasome, has been emphasized recently. NLRP3 is a critical pattern recognition receptor involved in the expression of immune responses and has been found to play a significant role in the development of various immunological and neurological disorders such as multiple sclerosis, ulcerative colitis, gout, diabetes, and AD. It is a multimeric protein which releases various cytokines and causes caspase-1 activation through the process known as pyroptosis. Increased levels of cytokines (IL-1ß and IL-18), caspase-1 activation, and neuropathogenic stimulus lead to the formation of proinflammatory microglial M1. Progressive researches have also shown that besides loss of neurons, the pathophysiology of AD primarily includes amyloid beta (Aß) accumulation, generation of oxidative stress, and microglial damage leading to activation of NLRP3 inflammasome that eventually leads to neuroinflammation and dementia. It has been suggested in the literature that suppressing the activity of the NLRP3 inflammasome has substantial potential to prevent, manage, and treat Alzheimer's disease. The present review discusses the functional composition, various models, signaling molecules, pathways, and evidence of NLRP3 activation in AD. The manuscript also discusses the synthetic drugs, their clinical status, and projected natural products as a potential therapeutic approach to manage and treat NLRP3 mediated AD.

N-acetyl-L-cysteine ameliorates mitochondrial dysfunction in ischemia/reperfusion injury via attenuating Drp-1 mediated mitochondrial autophagy.

BACKGROUND AND PURPOSE: Ischemic reperfusion (I/R) injury causes a wide array of functional and structure alternations of mitochondria, associated with oxidative stress and increased the severity of injury. Despite the previous evidence for N-acetyl-L-cysteine (NAC) provide neuroprotection after I/R injury, it is unknown to evaluate the effect of NAC on altered mitochondrial autophagy forms an essential axis to impaired mitochondrial quality control in cerebral I/R injury. METHODS: Male wistar rats subjected to I/R injury were used as transient Middle Cerebral Artery Occlusion (tMCAO) model. After I/R injury, the degree of cerebral tissue injury was detected by infarct volume, H&E staining and behavioral assessment. We also performed mitochondrial reactive oxygen species and mitochondrial membrane potential by flow cytometry and mitochondrial respiratory complexes to evaluate the mitochondrial dysfunction. Finally, we performed the western blotting analysis to measure the apoptotic and autophagic marker. RESULTS: We found that NAC administration significantly ameliorates brain injury, improves neurobehavioral outcome, decreases neuroinflammation and mitochondrial mediated oxidative stress. We evaluated the neuroprotective effect of NAC against neuronal apoptosis by assessing its ability to sustained mitochondrial integrity and function. Further studies revealed that beneficial effects of NAC is through targeting the mitochondrial autophagy via regulating the GSK-3ß/Drp1mediated mitochondrial fission and inhibiting the expression of beclin-1 and conversion of LC3, as well as activating the p-Akt pro-survival pathway. CONCLUSION: Our results suggest that NAC exerts neuroprotective effects to inhibit the altered mitochondrial changes and cell death in I/R injury via regulation of p-GSK-3ß mediated Drp-1 translocation to the mitochondria.

Identification of novel small molecule non-peptidomimetic inhibitor for prolyl oligopeptidase through in silico and in vitro approaches.

Prolyl oligopeptidase (POP) enzyme has been studied for various disorders, viz. Schizophrenia, Alzheimer's, Parkinson's, Depression, Inflammation, etc., for three decades, but no drug has passed through the clinical trials, possibly because of indigent pharmacokinetics. This might have been a result of similar structures of drug candidates. This study aimed at identifying novel small non-peptidomimetic inhibitors for POP enzyme that could serve as a lead for developing newer drugs. Structure-based virtual screening of molecules of MolMall database was conducted on the POP enzyme (PDB ID 3DDU) to identify potential hits. The hits identified were subjected to computational pharmacokinetic screening followed by molecular mechanics/generalized Born and surface area studies to estimate the binding free energy of the docked complexes. After that, nine hits were selected and tested for POP inhibitory activity, among which one compound MM 4 was found to be most potent with EC50 of 100 µM. Compound MM 4 was further subjected to molecular dynamics simulations to study the overall stability of the ligand-protein complex. The compound interacted strongly with catalytic amino acid Arg643 by forming salt and water bridges; it also interacted well with amino acids Phe173, Arg252 and Met235. This study provides a lead molecule for further development of POP inhibitors.Communicated by Ramaswamy H. Sarma.

Nerolidol attenuates cyclophosphamide-induced cardiac inflammation, apoptosis and fibrosis in Swiss Albino mice.

Incidence and prevalence of cancer is an alarming situation globally. For the treatment of cancer many anticancer drugs have been developed but, unfortunately, their potential cardiotoxic side effects raised serious concerns about their use among clinicians. Cyclophosphamide is a potent anticancer and immunosuppressant drug but its use is limited due to cardiotoxic side effect. Thus, there is a need for the development of certain drug which can reduce cardiotoxicity and can be used as an adjuvant therapy in cancer patients. In this direction we, therefore planned to evaluate nerolidol (NER) for its cardioprotective potential against cyclophosphamide-induced cardiotoxicity in Swiss Albino mice. Animals were divided into 6 groups. Vehicle control; Cyclophosphamide (CP 200); NER 400 per se; NER 200 + CP 200; NER 400 + CP 200; and fenofibrate (FF 80) + CP 200. Dosing was done for 14 days along with a single dose of CP 200 on the 7th day. On 15th day animals were sacrificed and various biochemical parameters pertaining to oxidative stress, nitrative stress, inflammation, apoptosis and fibrosis were estimated in the blood and heart tissues. Histopathological analysis (H & E and Masson's trichrome staining); ultrastructural analysis (transmission electron microscopy) and immunohistochemical analysis were also performed along with mRNA expression and molecular docking to establish the cardioprotective potential of nerolidol. Nerolidol acted as a potent cardioprotective molecule and attenuated CP-induced cardiotoxicity.

Nerolidol ameliorates cyclophosphamide-induced oxidative stress, neuroinflammation and cognitive dysfunction: Plausible role of Nrf2 and NF- κB.

AIM: Cyclophosphamide (CP) is a potent anticancer and immunosuppressant drug. Studies have shown significant oxidative stress and cognitive impairment but neuroinflammatory and histological aberrations with its administration is underexplored. Nerolidol (NER) is a lipophilic bioactive molecule with antioxidant and anti-inflammatory properties but it has not been explored for neuroprotective potential in CP-induced neurotoxic manifestations. Therefore, in the present study, we aimed to evaluate the neuroprotective potential of NER in CP-induced neuroinflammation and associated comorbid conditions like depression and cognitive dysfunctions. MATERIALS AND METHOD: In-silico study using Schrödinger software was used to assess the binding affinity of NER with Nrf2. In the In vivo study, NER 200 and 400 mg/kg p.o. were given from 1st day to 14th day. CP 200 mg/kg, i.p., was administered on the 7th day. After 24 h of the last dosing, neurobehavioral tests like spontaneous body alternation, passive avoidance and forced swim test were performed. On completion of study, mice were sacrificed, hippocampus and cortex were removed for biochemical estimations, histopathology and immunohistochemistry of p65 NF- κB and Nrf2. KEY FINDINGS: In-silico study showed significant binding of NER into the pocket domain of Nrf2. In-vivo study showed protective effect of NER against CP-induced neuroinflammation, oxidative stress, cognitive impairment and structural abnormalities in the hippocampus and cortex regions. SIGNIFICANCE: Findings of the study suggested that NER is a potential therapeutic molecule which can mitigate CP-induced neurotoxic manifestations via Nrf2 and NF-κB pathway. However, more detailed studies are needed to explicate the mechanism underlying its neuroprotective effect.

Effect of melatonin on Aß42 induced changes in the mitochondrial function related to Alzheimer's disease in Drosophila melanogaster.

Alzheimers's disease is one of the alarming neurodegenerative disease and it is of global concern.The hallmarks of the disease are the amyloid beta (Aß) aggregation and presence of neurofibrillary tangles (NFTs). The interaction of Aß with macromolecular targets affects the normal cellular functions. The amyloid peptide interaction with cellular surfaces may trigger the intracellular cascades of signalling. Interaction of Aß with mitochondria leads to the generation of free radicals. Many studies have suggested the involvement of mitochondrial dysfunction in Alzheimer's disease. Melatonin prevents mitochondria stress and by means of activating the antioxidant systems it protects the death of neurons. Although the study have been already conducted on Aß42 infused or injury induced animal models but till date there is no reports of such studies on transgenic model of Drosophila melanogaster. In the present study, we have taken UAS/Gal4 system for the development of transgenic flies that overexpress Aß42 in the brain of Drosophila. With the help of these transgenic flies we have analyse different experiments like behavioural parameters, oxidative stress parameters and protein expression through western blotting in the presence of melatonin. We have found that melatonin significantly ameliorated the toxicity caused by the Aß42 overexpression. Thus the present study could be beneficial to find out the role of melatonin in transgenic flies overexpressing human Aß42.

Unveiling novel diphenyl-1H-pyrazole based acrylates tethered to 1,2,3-triazole as promising apoptosis inducing cytotoxic and anti-inflammatory agents.

Meagre and suboptimal therapeutic response along with the side effect profile associated with the existing anticancer therapy have necessitated the development of new therapeutic modalities to curb this disease. Bearing in mind the current scenario, a series of 1,2,3-triazole linked 3-(1,3-diphenyl-1H-pyrazol-4-yl)acrylates was synthesized following a multi-step reaction scheme. Initial screening for anticancer potential was done by in vitro sulforhodamine B assay against four human cancer cell lines- MCF-7 (breast), A549 (Lung) and HCT-116 and HT-29 (Colon). On evaluation, several compounds showed promising growth inhibition against all the cell lines, particularly compounds 6e, 6f and 6n. Among them, compound 6f displayed IC50 values of 1.962, 3.597, 1.764 and 4.496 µM against A549, HCT-116, MCF-7 and HT-29 cell lines respectively. Furthermore, the apoptosis inducing potential of the compounds was determined by Hoechst staining and DNA fragmentation assay. Colony formation inhibition assay was also carried out to determine the long term cytotoxic potential of the molecules. Moreover, compounds 6e, 6f and 6n were also evaluated for anti-inflammatory activity by protein albumin denaturation assay and red blood cell membrane stabilizing assay.

Pyrrole: An insight into recent pharmacological advances with structure activity relationship.

Pyrrole is a heterocyclic ring template with multiple pharmacophores that provides a way for the generation of library of enormous lead molecules. Owing to its vast pharmacological profile, pyrrole and its analogues have drawn much attention of the researchers/chemists round the globe to be explored exhaustively for the benefit of mankind. This review focusses on recent advancements; pertaining to pyrrole scaffold, discussing various aspects of structure activity relationship and its bioactivities.

Synthesis of Hybrids of Dihydropyrimidine and Pyridazinone as potential Anti-Breast Cancer Agents.

BACKGROUND: Different 3-aroylpropionic acids and dihydropyrimidine hydrazine derivatives were condensed together to yield a series of dihydropyrimidine and pyridazinone hybrids (5a-u). OBJECTIVE: This was done in order to develop therapeutic agents for the treatment of breast cancer with improved Cycloxygenase-2 (COX-2) selectivity. In-vitro anticancer evaluation for these compounds was done against human breast cancer cell lines (MCF-7, MDA-MB-231) and normal human keratinocytes (HaCaT). CONCLUSION: Amongst all the developed analogs, compound 5l emerged as the most potent agent against both these cell lines with IC50 values of 3.43 and 2.56 µM respectively. The synthesized compounds were also evaluated for COX-2 selectivity. To observe the binding pattern of the compounds with COX-2, a docking study was performed using PDB ID: 1CX2.

Therapeutic evolution of benzimidazole derivatives in the last quinquennial period.

Benzimidazole, a fused heterocycle bearing benzene and imidazole has gained considerable attention in the field of contemporary medicinal chemistry. The moiety is of substantial importance because of its wide array of pharmacological activities. This nitrogen containing heterocycle is a part of a number of therapeutically used agents. Moreover, a number of patents concerning this moiety in the last few years further highlight its worth. The present review covers the recent work published by scientists across the globe during last five years.

The therapeutic journey of pyridazinone.

Pyridazinones have drawn a substantial attention within the field of research analysis and development. The moiety is a subject matter of intensive research because of its wide spectrum of biological activities and therapeutic applications. The synthesis of pyridazinone and investigation of their chemical and biological activities have gained additional importance in recent years. In this review, we have compiled and discussed various biological and therapeutic potential of pyridazinone derivatives.

4, 5-Dihydrooxazole-pyrazoline hybrids: Synthesis and their evaluation as potential antimalarial agents.

A new series of oxazoline-pyrazoline hybrids (4a-p) were synthesized by condensation reaction of substituted oxazoline based chalcones (3a-m) and substituted hydrazines in methanol. Some of the compounds exhibited promising in vitro antimalarial activity for chloroquine sensitive CQ(S) (3D7) strain and chloroquine resistant CQ(R) (RKL9) strain. The most potent analogue 4i (IC50 0.322 µg/ml) exhibited significant in vivo antimalarial potential against Plasmodium berghei mouse model. The stable complex of 4i with hematin (1:1 stoichiometry) suggests that heme may be one possible target for these hybrid compounds. The study has revealed potential of title compounds as lead for the development of antimalarial agents.

Pharmacophore based virtual screening, synthesis and SAR of novel inhibitors of Mycobacterium sulfotransferase.

A planned 3D-pharmacophore mapping was carried out on the basis of chemical features associated with known Stf0 inhibitors. Four models (model 1-4) were obtained after GASP (Genetic Algorithm Similarity Program) refinement of seven models (D-1 to D-7) generated by using DISCOtech. The selected GASP model-1 has two hydrogen bond acceptor, two hydrogen bond donor and four hydrophobic points. This model was used for virtual screening (VS) of large public databases along with in house generated knowledge base database. VS followed by docking of selected compounds on Stf0 active site was carried and pose analysis done. Seven hits were identified after all the computational studies, of which 2 hits were synthesized along with their analogs and evaluated for antitubercular activity. IH-45 was found promising after in vitro assay.

Pyrazolines: a biological review.

Pyrazoline is an important five membered nitrogen heterocycle, which has been extensively researched upon. The ring is quite stable and has inspired chemists to carry out various structural variations in the ring. This has propelled the development of distinct pyrazolines with an array of pharmacological activities viz. anti-inflammatory, analgesic, antimicrobial, anticancer, antidepressant etc. The review aims at highlighting this pharmacological diversity of pyrazolines. The review is a gist of latest work done describing the pharmacological aspects and potential of pyrazoline ring.

Recent updates on biological activities of oxadiazoles.

Among the plethora of heterocyclic nucleus discovered, the oxadiazoles have also been explored extensively. The oxadiazole structure has been demonstrated to bear important biological activities such as anti-cancer, antiinflammatory, anti-tuberculosis, anti-malarial and anti-schistosomiasis etc. The presence of oxadiazole motifs in diverse types of compounds proves its importance in the field of medicinal chemistry. This review is complementary to earlier reviews and covers recent updates of various pharmacological aspects of oxadiazoles. To help the reader better know the context for these approaches, a summary of various aspects of background of related topic is presented.

Synthesis and biological evaluation of some new pyridazinone derivatives.

A series of pyridazinone derivatives (19-34) were synthesized with an aim to synthesize safer anti-inflammatory agents. The compounds were evaluated for their anti-inflammatory, analgesic, ulcerogenic and lipid peroxidation (LPO) actions. The percentage inhibition in edema at different time intervals indicated that compounds 20, 26, 28 and 34 exhibited good anti-inflammatory potential, comparable with that of ibuprofen (85.77%) within a range of 67.48-77.23%. The results illustrate that 5-(4-fluoro-benzyl)-3-(4-chloro-phenyl)-1,6-dihydro-6-pyridazinone (26) and 5-(4-chloro-benzyl)-3-(4-chloro-phenyl)-1,6-dihydro-6-pyridazinone (20) showed best anti-inflammatory activity. Furthermore, activity is more in case of chloro substitution as compared with methyl-substitution. The compounds synthesized were also evaluated for their ulcerogenic and LPO action and showed superior gastrointestinal safety profile along with reduction in LPO as compared with that of the ibuprofen.