Macromolecules: Synthesis, antimicrobial, POM analysis and computational approaches of some glucoside derivatives bearing acyl moieties.

Macromolecules i.e., carbohydrate derivatives are crucial to biochemical and medical research. Herein, we designed and synthesized eight methyl α-D-glucopyranoside (MGP) derivatives (2-8) in good yields following the regioselective direct acylation method. The structural configurations of the synthesized MGP derivatives were analyzed and verified using multiple physicochemical and spectroscopic techniques. Antimicrobial experiments revealed that almost all derivatives demonstrated noticeable antifungal and antibacterial efficacy. The synthesized derivatives showed minimum inhibitory concentration (MIC) values ranging from 0.75 µg/mL to 1.50 µg/mL and minimum bactericidal concentrations (MBCs) ranging from 8.00 µg/mL to 16.00 µg/mL. Compound 6 inhibited Ehrlich ascites carcinoma (EAC) cell proliferation by 10.36% with an IC50 of 2602.23 µg/mL in the MTT colorimetric assay. The obtained results were further rationalized by docking analysis of the synthesized derivatives against 4URO and 4XE3 receptors to explore the binding affinities and nonbonding interactions of MGP derivatives with target proteins. Compound 6 demonstrated the potential to bind with the target with the highest binding energy. In a stimulating environment, a molecular dynamics study showed that MGP derivatives have a stable conformation and binding pattern. The MGP derivatives were examined using POM (Petra/Osiris/Molinspiration) bioinformatics, and as a result, these derivatives showed good toxicity, bioavailability, and pharmacokinetics. Various antifungal/antiviral pharmacophore (Oδ-, O'δ-) sites were identified by using POM investigations, and compound 6 was further tested against other pathogenic fungi and viruses, such as Micron and Delta mutants of SARS-CoV-2.

Tropolones and Thailandepsin B as Lead-like Natural Compounds in the Development of Potent and Selective Histone Deacetylase Inhibitors.

BACKGROUND: Tropolone and thailandepsin B are naturally occurring substances that are primarily isolated from fungi and plants, although they can also be found in certain bacteria. Tropolones belong to an important class of aromatic compounds with a seven-membered nonbenzenoid ring structure. Thailandepsins are a group of natural products that were initially discovered in the culture broth of the Gram-negative bacterium Burkholderia thailandensis. Tropolonebased structures have been identified in over 200 natural compounds, ranging from simple tropolone derivatives to complex multicyclic systems like pycnidione and pyrerubrine A. These natural compounds exhibit a diverse range of pharmacological effects, including antibacterial, antifungal, insecticidal, phytotoxic, anti-inflammatory, antimitotic, anti-diabetic, enzyme inhibitory, anticancer, cytoprotective, and ROS scavenging properties. It is worth noting that thujaplicane, a compound similar to tropolone, displays all of the listed biological activities except for antimitotic action, which has only been observed in one natural tropolone compound, colchicine. Tropolone can be synthesized from commercially available seven-membered rings or derived through various cyclization and cycloaddition reactions. Thailandepsin B, on the other hand, can be synthesized by macro-lactonization of the corresponding secoacid, followed by the formation of internal disulfide bonds. It is important to mention that thailandepsin B exhibits different selective inhibition profiles compared to FK228. OBJECTIVE: We investigated the HDAC inhibitory activity of the Tropolones and Thailandepsin B and discussed the biosynthesis of the naturally occurring compounds and their synthetic scheme. RESULTS AND CONCLUSION: It has been observed that Tropolone derivatives act as isoenzyme-selective inhibitors of proven anticancer drug targets, histone deacetylases (HDACs). Some monosubstituted tropolones show remarkable levels of selectivity for HDAC2 and strongly inhibit the growth of T-lymphocyte cell lines. And Thailandepsins have different selective inhibition profiles than FK228. They exhibit comparable inhibitory activities to FK228 against human HDAC1, HDAC2, HDAC3, HDAC6, HDAC7, and HDAC9, but less potent inhibitory activities than FK228 toward HDAC4 and HDAC8, the latter of which may be useful. Thailandepsins possess potent cytotoxic activities toward some types of cell lines.

Potential of Synthetic and Natural Compounds as Novel Histone Deacetylase Inhibitors for the Treatment of Hematological Malignancies.

Histone deacetylases (HDACs) and histone acetyltransferases (HATs) are enzymes that remove or add acetyl groups to lysine residues of histones, respectively. Histone deacetylation causes DNA to more snugly encircle histones and decreases gene expression, whereas acetylation has the opposite effect. Through these small alterations in chemical structure, HATs and HDACs regulate DNA expression. Recent research indicates histone deacetylase inhibitors (HDACis) may be used to treat malignancies, including leukemia, B-cell lymphoma, virus-associated tumors, and multiple myeloma. These data suggest that HDACis may boost the production of immune-related molecules, resulting in the growth of CD8-positive T-cells and the recognition of nonreactive tumor cells by the immune system, thereby diminishing tumor immunity. The argument for employing epigenetic drugs in the treatment of acute myeloid leukemia (AML) patients is supported by evidence that both epigenetic changes and mutations in the epigenetic machinery contribute to AML etiology. Although hypomethylating drugs have been licensed for use in AML, additional epigenetic inhibitors, such as HDACis, are now being tested in humans. Preclinical studies evaluating the efficacy of HDACis against AML have shown the ability of specific agents, such as anobinostat, vorinostat, and tricostatin A, to induce growth arrest, apoptosis, autophagy and cell death. However, these inhibitors do not seem to be successful as monotherapies, but instead achieve results when used in conjunction with other medications. In this article, we discuss the mounting evidence that HDACis promote extensive histone acetylation, as well as substantial increases in reactive oxygen species and DNA damage in hematological malignant cells. We also evaluate the potential of various natural product-based HDACis as therapeutic agents to combat hematological malignancies.

Histone Deacetylase Inhibitors as Cognitive Enhancers and Modifiers of Mood and Behavior.

BACKGROUND: Epigenetic regulation of gene signalling is one of the fundamental molecular mechanisms for the generation and maintenance of cellular memory. Histone acetylation is a common epigenetic mechanism associated with increased gene transcription in the central nervous system (CNS). Stimulation of gene transcription by histone acetylation is important for the development of CNS-based long-term memory. Histone acetylation is a target for cognitive enhancement via the application of histone deacetylase (HDAC) inhibitors. The promising potential of HDAC inhibitors has been observed in the treatment of several neurodevelopmental and neurodegenerative diseases. OBJECTIVE: This study assessed the current state of HDAC inhibition as an approach to cognitive enhancement and treatment of neurodegenerative diseases. Our analysis provides insights into the mechanism of action of HDAC inhibitors, associated epigenetic priming, and describes the therapeutic success and potential complications after unsupervised use of the inhibitors. RESULTS AND CONCLUSION: Several chromatin-modifying enzymes play key roles in the regulation of cognitive processes. The importance of HDAC signaling in the brain is highlighted in this review. Recent advancements in the field of cognitive epigenetics are supported by the successful development of various HDAC inhibitors, demonstrating effective treatment of mood-associated disorders. The current review discusses the therapeutic potential of HDAC inhibition and observed complications after mood and cognitive enhancement therapies.

Gossypol and Its Natural Derivatives: Multitargeted Phytochemicals as Potential Drug Candidates for Oncologic Diseases.

Despite the vast amounts of research and remarkable discoveries that have been made in recent decades, cancer remains a leading cause of death and a major public health concern worldwide. Gossypol, a natural polyphenolic compound derived from the seeds, roots, and stems of cotton (Gossypium hirsutum L.), was first used as a male contraceptive agent. Due to its diverse biological properties, including antifertility, antiviral, antioxidant, antibacterial, antimalarial, and most notably antitumor activities, gossypol has been the subject of numerous studies. Nevertheless, no systematic review has been performed that analyzes the antineoplastic potential of gossypol and related natural compounds in an organ-specific manner while delineating the molecular mechanisms of action. Hence, we have performed an extensive literature search for anticancer properties of gossypol and their natural derivatives against various types of cancer cells utilizing PubMed, ScienceDirect, Google Scholar, and Scopus. The sources, distribution, chemical structure, and toxicity of gossypol and its constituents are briefly reviewed. Based on emerging evidence, gossypol and related compounds exhibit significant antineoplastic effects against various cancer types through the modulation of different cancer hallmarks and signaling pathways. Additionally, the synergistic activity of gossypol and its derivatives with chemotherapeutic agents has been observed. Our evaluation of the current literature suggests the potential of gossypol and its derivatives as multitargeting drug candidates to combat multiple human malignancies.

A review on synthetic strategy, molecular pharmacology of indazole derivatives, and their future perspective.

With different nitrogen-containing heterocyclic moieties, Indazoles earn one of the places among the top investigated molecules in medicinal research. Indazole, an important fused aromatic heterocyclic system containing benzene and pyrazole ring with a chemical formula of C7 H6 N2 , is also called benzopyrazole. Indazoles consist of three tautomeric forms in which 1H-tautomers (indazoles) and 2H-tautomers (isoindazoles) exist in all phases. The tautomerism in indazoles greatly influences synthesis, reactivity, physical and even the biological properties of indazoles. The thermodynamic internal energy calculation of these tautomers points view 1H-indazole as the predominant and stable form over 2H-indazole. The natural source of indazole is limited and exists in alkaloidal nature (i.e., nigellidine, nigeglanine, nigellicine, etc.) found from Nigella plants. Some of the FDA-approved drugs like Axitinib, Entrectinib, Niraparib, Benzydamine, and Granisetron are being used to treat renal cell cancer, non-small cell lung cancer (NSCLC), epithelial ovarian cancer, chronic inflammation, chemotherapy-induced nausea, vomiting, and many more uses. Besides all these advantages regarding its biological activity, the main issue about indazoles is the less abundance in plant sources, and their synthetic derivatives also often face problems with low yield. In this review article, we discuss its chemistry, tautomerism along with their effects, different schematics for the synthesis of indazole derivatives, and their different biological activities.

Combination Therapy of Ledipasvir and Itraconazole in the Treatment of COVID-19 Patients Coinfected with Black Fungus: An In Silico Statement.

The manuscript mainly aimed at providing clues on improving the innate immunity of coronavirus patients and safeguarding them from both new mutant strains and black fungus infections. Coronavirus is readily mutating from one variant to another. Among the several variants, we selected SARS-CoV-2 B.1.1.7 in this study. Upon infection of any virus, ideally, the phagocytic cells of the host engulf and destroy the virus by a mechanism called phagocytosis. However, compromised immunity impairs phagocytosis, and thus, restoring the immune system is crucial for a speedy recovery of infected patients. The autophagy and activation of Toll-like receptor-4 are the only ways to restore innate immunity. Recently, immunocompromised COVID-19 patients have been suffering from the coinfection of black fungus. Rhizomucor, a black fungus species, causes more than 75% of cases of mucormycosis. Here, we present the results of molecular docking studies of sixty approved antiviral drugs targeting receptors associated with the SARS-CoV-2 B 1.1.7 variant (PDB id: 7NEH), activating the innate immune system (PDB id: 5YEC and 5IJC). We also studied the twenty approved antifungal drugs with Rhizomucor miehei lipase propeptide (PDB id: 6QPR) to identify the possible combination therapy for patients coinfected with coronavirus and black fungus. The ledipasvir showed excellent docking interactions with the 7NEH, 5YEC, and 5IJC, indicating that it is a perfect candidate for the treatment of COVID-19 patients. Itraconazole showed significant interaction with 6QPR of Rhizomucor miehei, suggesting that itraconazole can treat black fungus infections. In conclusion, the combination therapy of ledipasvir and itraconazole can be a better alternative for treating COVID-19 patients coinfected with black fungus.

Importance of Indazole against Neurological Disorders.

Indazole is a nitrogen-containing bicyclic compound, having three tautomeric forms: 1Hindazole, 2H-indazole, and 3H-indazole. Mostly, they are considered as 1H-indazole tautomeric forms, although they have the potential to tautomerism to 2H- and 3H-indazole forms. Indazoles are involved in a wide variety of biological and enzymatic processes. Therefore, they exhibit a series of pharmacological activities. Indazoles show potent activities against neurological disorders such as Parkinson's disease (PD), Alzheimer's disease (AD), mood disorders, etc., by inhibiting different signaling pathways and the generation of neurotransmitters and activation of enzyme activity. They effectively prevent neurological diseases by different mechanisms, such as by inhibiting the monoamine oxidase (MAO) and kinase enzymes like Glycogen synthase kinase 3 (GSK3), and leucinerich repeat kinase enzyme 2 (LRRK2). In this article, we have discussed multiple causative strategies of indazole to treat neurological diseases. This has aroused special attention in the discovery of the novel indazoles and their biological activities.

Indazole-based microtubule-targeting agents as potential candidates for anticancer drugs discovery.

Tremendous research is focused on developing novel drug candidates targeting microtubules to inhibit their function in several cellular processes, including cell division. In this regard, several indazole derivatives were sought to target the colchicine binding site on the ß-tubulin, a crucial protein required to form microtubules, to develop microtubule targeting agents. Even though there are several reviews on the indazole-based compounds, none of them focused on using indazole scaffold to develop microtubule targeting agents. Therefore, this review aims to present the advances in research on compounds containing indazole scaffolds as microtubule targeting agents based on the articles published in the last two decades. Among the articles reviewed, we found that compounds 6 and 7 showed the lowest IC50 values of 0.6 âˆ¼ 0.9 nM in the cell line studies, making them the strongest indazole derivatives that target microtubules. The compounds 30, 31, 37 (IC50 = ∼ 1 nM) and compounds 8, 38 (IC50 = ∼ 2 nM) have proved to be potent microtubule inhibitors. The compounds 18, 31, 44, 45 also showed strong anticancer activity (IC50 = ∼ 8 nM). It is important to notice that except for compounds 9, 12, 13, 15, and SRF, the top activity compounds including 6, 7, 8, 10, 11, 30, 31, 37, 44, and 45 contain 3,4,5­trimethoxyphenyl substitution similar to that of colchicine. Therefore, it appears that the 3,4,5­trimethoxyphenyl substituent on the indazole scaffold is crucial for targeting CBS.

Indazole Derivatives Effective against Gastrointestinal Diseases.

BACKGROUND: In this fast-growing lifestyle, humans are in the race against time to cope up with busy schedule. Less exercise, consumption of high calorie-low fiber food and stress take us one step closer towards digestive dysfunction. Dysfunctional digestive system causes various gastrointestinal disorders like constipation, IBS, UC, diarrhea, gastrointestinal tract immobility, hyperglycemia, hemorrhoids, fistula, anal fissures, stomach cancer, hepatocellular carcinoma, pancreatic cancer, colon cancer and metabolic syndrome. Amongst various natural and synthetic indazole derivatives nigellicine, nigellamine, nigellidine, zanubrutinib and SCH772984 showed prominent results to cure various gastrointestinal disorders. OBJECTIVES: In this manuscript, we focus on the importance of indazole derivatives in the treatment of various gastrointestinal diseases. RESULTS AND CONCLUSION: In the treatment of IBS, four positions (R1, R2, R3 and R4) of indazole were mainly substituted with aromatic aldehyde/substituted methyl, aromatic acid/formamide, benzamide/ sulfonamide and methyl groups, respectively. In case of diarrhea and metabolic syndrome treatment, substitutions with benzyl/isopropyl/acetaldehyde (R1 position) and carboxamide/ formamide (R2 position) of indazole play a critical role. Also, in the treatment of diabetes melitus, all six positions of indazole derivative were substituted with substituted aryl/alkyl/aromatic acid, substituted formamide, substituted acetamide/hydrazide group, halo aryl, substituted aryl/aromatic acid and a long chain of alkyl-aryl alcohol groups, respectively. In the treatment of gastrointestinal cancers, all six positions of indazole derivative were substituted with benzylamide (R1), octanediamide/ benzamide/formamide (R2), carbaldehyde (R4) and substituted phenyl (R5 and R6) groups, respectively. Six receptors (6NP0, 2YME, 4EFU, 4WZ8, 5U4W and 7KKP) associated with GI disorders (co-crystallized with indazole derivative) were identified. Analysis of the receptors showed that co-crystalized ligand molecules were well-interacted with receptors via pie-pie interaction, coordinate and sigma bonding within 4 Å distance. As per Ramachandran plot analysis, more than 90% of the amino acid residues were present in the most favored region. So, if sufficient focuses are imposed on the development of newer indazole derivatives to treat gastrointestinal diseases, it will work as a boon to society.

Role of γ-Secretase Inhibitors for the Treatment of Diverse Disease Conditions through Inhibition of Notch Signaling Pathway.

γ-secretase is an intramembrane protease sub-assembly that sunders transmembrane proteins. It is involved in intramembrane proteolysis and also contributes to the regeneration of transmembrane protein. The amyloid precursor proteins (APPs) are typical γ-secretase substrates. These proteins are cleaved to produce 36-43 amyloid-beta (Aß) amino acid peptides. Abnormal folding of these proteins fragments leads to amyloid plaques, which are frequently encountered in Alzheimer's disease. Some Type I class of integral membrane proteins is processed under the influence of γ-secretase, such as receptor tyrosine-protein kinase erbB4 and CD44 glycoprotein. γ-Secretase is being explored in several diseases as a clinical goal. Both γ-secretase inhibitors (GSIs) and γ-secretase modulators (GSMs) are being evaluated for this purpose. A large amount of γ-secretase inhibitors (GSIs) from peptide to non-peptide have been disclosed, offering several lead compounds for the design and optimization of γ-secretase targets, but most GSIs lack sufficient potency, exhibit low penetration in the brain, and manifest low selectiveness. γ-secretase inhibitors are obliquely a regulator of a γ-secretase substrate Notch, and valuable in the development of ß-amyloid peptide (Aß). These γ-secretase inhibitors block the Notch signaling pathway in autoimmune and lymphoproliferative disorders, like autoimmune lymphoproliferative syndrome (ALPS) and systemic lupus erythematosus (SLE), and perhaps even in cancerous cell proliferation, angiogenesis, and cellular differentiation of human-induced pluripotent stem cells (hiPSC). The current review portrays the mechanism, regulation, and inhibition of γ-secretase in the management of a wide assortment of diseases.

Glycogen Synthase Kinase-3 (GSK-3) Inhibitors as a New Lead for Treating Breast and Ovarian Cancer.

A serine/threonine-protein kinase, recognized as Glycogen Synthase Kinase-3 (GSK-3), is documented as a regulator of assorted cellular roles. GSK-3 activates by phosphorylation and thereby controls the action of many physiological, messenger, and membrane-bound structures. GSK-3α and GSK-3ß are two vastly homologous forms of GSK-3 in mammals. Recent information has recommended that GSK-3ß is a constructive controller of cancer cell proliferation and a promising key target against cancer cells. GSK-3 is overexpressed in various tumor types, including ovarian tumors. In human breast carcinoma, it has been revealed that the overexpression of GSK-3ß was linked with breast cancer patients. The inhibition of GSK-3 or inhibitors of GSK-3 is a promising therapeutic tactic to overcome breast and ovarian cancer. This article features an important aspect of inhibitors of Glycogen Synthase Kinase-3 as a new lead for treating breast and ovarian Cancer.

Gamma Secretase Inhibitor: Therapeutic Target via NOTCH Signaling in T Cell Acute Lymphoblastic Leukemia.

BACKGROUND: T-cell acute lymphoblastic leukemia (T-ALL) is a diseased condition of bone marrow and lymphoblast, mainly expressed on T-cell immune phenotype. Diagnosis of TALL patients shows the burden of a large tumour and leukemia cells in the peripheral blood vessel which often infiltrates into the central nervous system. OBJECTIVE: Chemotherapy is considered the primary mode of treatment for this disease, but recent advancements in the molecular understanding of the disease, including NOTCH1 signaling, could offer some alternatives. NOTCH signaling undergoes a non-regulated mutation at NOTCH1 in most T-ALL. Gamma-secretase (GS) plays a key role in blocking of proteolytic activation of NOTCH receptors, which could potentially be a new targeted therapy for this type of leukaemia. This study mainly aims to outline the role of γ-secretase inhibitors via NOTCH signaling in TALL. RESULTS: The role of GSI (γ-secretase inhibitor) in most T-ALL cell lines has been linked to the targeting pathway of NOTCH signaling. Mutation at NOTCH1 has however not served as a predictor of γ-secretase inhibitor sensitivity because of several factors, including gene expression of NOTCH pathway activity. Therefore, despite the promising outcome of this approach in NOTCH-1 activated T-ALL, not all patients with this condition are expected to respond. CONCLUSION: Long-term therapeutic success against cancerous cells is rarely achieved with monotherapy, and even targeting investigational pathways such as NOTCH may require a combination regimen. Ultimately, the optimised use of these new therapeutic agents may become the next tool in our search for an effective 'individualized medicine'.

GSK-3 Inhibitors as New Leads to Treat Type-II Diabetes.

In India as well as globally, diabetes is in a state of high risk and next to cardiovascular disease. As per the WHO, the risk of diabetes is expected to rise about 511 million by 2030. In quest of novel targets for type-2 diabetes, many targets were elucidated, such as Glycogen Synthase Kinase-3 (GSK-3), Dipeptidyl Peptidase (DPP-IV), PPAR-γ, α-Glucosidase, α-Amylase, GLP-1, and SGLT. Among the targets, GSK-3 was reported to be an effective target for the treatment of diabetes. In the metabolism of glycogen, GSK is a regulatory enzyme for the biosynthesis of glycogen (glycogenesis). It catalyzes the synthesis of a linear unbranched molecule with 1,4-α-glycosidic linkages. GSK-3 family has two isoenzymes, namely α and ß, which differ in their Nand C- terminal sequences and are semi-conservative multifunctional serine/threonine kinase enzymes. In this chapter, we discuss an overview of general diabetic mechanisms and how GSK-3 modulation may influence these processes. Mutation in the GSK-3 complex causes diabetes. Synthetic and natural scaffolds modulate GSK-3 against diabetes and leading to its optimization for the development of GSK-3 inhibitors. This review mainly focuses on the development of GSK-3 inhibitors and highlights current and potential future therapeutic approaches that support the notion of targeting glucose metabolism with novel antidiabetic agents.

Recent Advances in the Discovery of GSK-3 Inhibitors from Synthetic Origin in the Treatment of Neurological Disorders.

BACKGROUND: Glycogen synthase kinase 3 (GSK-3) is a serine/threonine kinase enzyme that controls neuronal functions such as neurite outgrowth, synapse formation, neurotransmission, and neurogenesis. The enzyme has two subunits as GSK-3α and GSK-3ß. 4ACC, 1Q3D, 3AFG, 1UV5, and 1Q5K are the important GSK-3 receptors isolated from Homo sapiens and Mus musculus. This enzyme mainly phosphorylates Tau protein with the increased amount in neuronal fibres together with beta-amyloid plaques that cause neuronal diseases like Alzheimer's, Parkinson's and many more. OBJECTIVE: We investigated the developments of various synthetic GSK-3 inhibitors responsible for the prevention and treatment of neurological disorders, like Alzheimer's disease, bipolar disorders, acting as antidepressants, neuroprotective, etc. Results and Conclusion: It has been observed that structures of the GSK-3 inhibitors are comprised of benzopyridine, benzothiazole, pyrazole, pyrazine, dioxolo-benzoxazine, oxadiazole, and benzimidazole in the skeletal with cyclopropyl amide, phenyl carbamothioate, 3-[(propan- 2-yl)oxy]propan-1-amine in the side chain. The molecules were evaluated against the effectivity of GSK-3, human adenosine kinase, cyclin-dependent kinase, and phosphodiesterase-4 along with tail suspension test forced swim test, percent neuronal survival and other cognitive behaviours. The observations confirmed the remarkable effects of the synthesized molecules to conquer Alzheimer, Parkinson's depression, psychosis and other forms of neurological disorders.

GSK-3 Inhibitors: A New Class of Drugs for Alzheimer's Disease Treatment.

Alzheimer's disease (AD), a chronic neurodegenerative disease, is the most common form of dementia that causes cognitive function impairment, including memory, thinking, and behavioral changes that ultimately lead to death. The overactivation of GSK-3, an enzyme from the proline/serine Ki NS family, has been associated with hyper-phosphorylation of tau proteins. The self- -assembly of hyper-phosphorylated tau proteins to form tangles of straight and helical filaments is known to be involved in AD. Therefore, GSK-3 has been considered a potential target of novel drug discovery for AD treatment. Research on the development of GSK-3 inhibitors has received enormous attention from the vast scientific community because they are targeted for AD and other diseases, including type 2 diabetes, cancers, stroke, Parkinson's disease and bipolar disorder. Various drugs of both synthetic and natural origins have been designed to inhibit GSK-3 activity. However, there is a need to develop novel drug candidates that can selectively inhibit GSK-3. Hence, this review summarizes the potential of GSK-3 inhibitors for AD therapy and discusses the structure- activity relationship of current drug molecules and the potential problems associated with them.

Insight γ-Secretase: Structure, Function, and Role in Alzheimer's Disease.

In neurodegenerative disorders, there is a progressive degeneration of the body, leading to the death of nerve cells. In this state, a patient gets affected day by day with mental weakness, dementia, and ataxia. Alzheimer's disease (AD) is the most common irreversible neurodegenerative brain disorder mainly affecting people over the age of 65. Many types of research suggest that the main culprit for AD is the aggregated form of a (39-43) amino acid peptide called amyloid beta. Amyloid beta (Aß) is generated by the action of beta-secretase and gamma-secretase on the larger glycoprotein. Gamma (γ) secretase is an intra-membrane protease complex that cleaves the single-- pass transmembrane protein, the amyloid precursor protein, and Notch. The γ-secretase complex contains presenilin, presenilin enhancer-2, anterior pharynx defective-1, and nicastrin. Any mutation in presenilin-1 or the cleavage of amyloid precursor protein by γ-secretase directly or indirectly is associated with AD. Therefore, the prevention of this enzyme is one of the solutions for AD. In this article, we discuss the γ-secretase complex and its inhibitors that can contribute to the prevention of AD.

Design, in silico studies, and synthesis of new 1,8-naphthyridine-3-carboxylic acid analogues and evaluation of their H1R antagonism effects.

New 1,8-naphthyridine-3-carboxylic acid derivatives were designed, synthesized and evaluated for their in vivo antihistaminic activity on guinea pig trachea by using chlorpheniramine as the standard drug. It was found that compound 5a1 displayed a promising bronchorelaxant effect in conscious guinea pigs using the in vivo model. A molecular docking study was performed to understand the molecular interaction and binding mode of the compounds in the active site of the H1 receptor. Furthermore, in silico computational studies were also performed to predict the binding modes and pharmacokinetic parameters of these derivatives. Prior to the start of experimental lab work, PASS software was used to predict the biological activities of these compounds. An in silico PASS, Swiss ADME assisted docking approach was found to be suitable to derive and synthesize effective antihistaminic agents for the present study.