The anti-Alzheimer potential of Tamarindus indica: an in vivo investigation supported by in vitro and in silico approaches

Antiplasmodial potential of phytochemicals from Citrus aurantifolia peels: a comprehensive in vitro and in silico study

Phytochemical investigation of Key lime (Citrus aurantifolia L., F. Rutaceae) peels afforded six metabolites, known as methyl isolimonate acetate (1), limonin (2), luteolin (3), 3`-hydroxygenkwanin (4), myricetin (5), and europetin (6). The structures of the isolated compounds were assigned by 1D NMR. In the case of limonin (2), further 1- and 2D NMR experiments were done to further confirm the structure of this most active metabolite. The antiplasmodial properties of the obtained compounds against the pathogenic NF54 strain of Plasmodium falciparum were assessed in vitro. According to antiplasmodial screening, only limonin (2), luteolin (3), and myricetin (5) were effective (IC50 values of 0.2, 3.4, and 5.9 µM, respectively). We explored the antiplasmodial potential of phytochemicals from C. aurantifolia peels using a stepwise in silico-based analysis. We first identified the unique proteins of P. falciparum that have no homolog in the human proteome, and then performed inverse docking, ΔGBinding calculation, and molecular dynamics simulation to predict the binding affinity and stability of the isolated compounds with these proteins. We found that limonin (2), luteolin (3), and myricetin (5) could interact with 20S a proteasome, choline kinase, and phosphocholine cytidylyltransferase, respectively, which are important enzymes for the survival and growth of the parasite. According to our findings, phytochemicals from C. aurantifolia peels can be considered as potential leads for the development of new safe and effective antiplasmodial agents.

Tamarind genus chemical composition and biological activities

Tamarindus indica L., the sole species in the genus Tamarind, which is a member of the subfamily Caesalpiniaceae in the family Leguminosae (Fabaceae), is extensively dispersed in many tropical and subtropical regions. This plant's Arabic name, Tamr Al-Hindi, is the basis for its English name, Tamarind. In traditional medicine, this genus has played a major role since the time of the ancient Egyptians. Folkloric medicine has traditionally used Tamarind to treat a variety of conditions, including diabetes mellitus, fever, malaria, ulcers, diarrhoea, dysentery and wounds. The primary bioactive components of this species, which have a variety of biological functions, have been identified as flavonoids, phenolic contents, sterols, triterpenes, fatty acids, sugars and other substances. Genus Tamarind has been shown to have anti-inflammatory, analgesic, anti-pyretic, antibacterial, hypolipidemic, anti-diabetic, hepatoprotective, anti-ulcerogenic and antioxidant properties. This article provides an overview of the identified chemicals from T. indica together with their stated biological activities.

New cytotoxic dammarane type saponins from Ziziphus spina-christi

Cancer is the world's second-leading cause of death. Drug development efforts frequently focus on medicinal plants since they are a valuable source of anticancer medications. A phytochemical investigation of the edible Ziziphus spina-christi (F. Rhamnaceae) leaf extract afforded two new dammarane type saponins identified as christinin E and F (1, 2), along with the known compound christinin A (3). Different cancer cell lines, such as lung cancer (A549), glioblastoma (U87), breast cancer (MDA-MB-231), and colorectal carcinoma (CT-26) cell lines, were used to investigate the extracted compounds' cytotoxic properties. Our findings showed significant effects on all the tested cell lines at varying concentrations (1, 5, 10, and 20 µg/mL). The three compounds exhibited potent activity at low concentrations (< 10 μg/mL), as evidenced by their low IC50 values. To further investigate the complex relationships between these identified cancer-relevant biological targets and to identify critical targets in the pathogenesis of the disease, we turned to network pharmacology and in silico-based investigations. Following this, in silico-based analysis (e.g., inverse docking, ΔG calculation, and molecular dynamics simulation) was performed on the structures of the isolated compounds to identify additional potential targets for these compounds and their likely interactions with various signalling pathways relevant to this disease. Based on our findings, Z. spina-christi's compounds showed promise as potential anti-cancer therapeutic leads in the future.

Vitis vinifera leaf extract liposomal Carbopol gel preparation's potential wound healing and antibacterial benefits: in vivo, phytochemical, and computational investigation

Vitis vinifera Egyptian edible leaf extract loaded on a soybean lecithin, cholesterol, and Carbopol gel preparation (VVL-liposomal gel) was prepared to maximize the in vivo wound healing and anti-MRSA activities for the crude extract, using an excision wound model and focusing on TLR-2, MCP-1, CXCL-1, CXCL-2, IL-6 and IL-1β, and MRSA (wound infection model, and peritonitis infection model). VVL-liposomal gel was stable with significant drug entrapment efficiency reaching 88% ± 3, zeta potential value ranging from -50 to -63, and a size range of 50-200 μm nm in diameter. The in vivo evaluation proved the ability of VVL-liposomal gel to gradually release the drugs in a sustained manner with greater complete wound healing effect and tissue repair after 7 days of administration, with a significant decrease in bacterial count compared with the crude extract. Phytochemical investigation of the crude extract of the leaves yielded fourteen compounds: two new stilbenes (1, 2), along with twelve known ones (3-14). Furthermore, a computational study was conducted to identify the genes and possible pathways responsible for the anti-MRSA activity of the isolated compounds, and inverse docking was used to identify the most likely molecular targets that could mediate the extract's antibacterial activity. Gyr-B was discovered to be the best target for compounds 1 and 2. Hence, VVL-liposomal gel can be used as a novel anti-dermatophytic agent with potent wound healing and anti-MRSA capacity, paving the way for future clinical research.

Abelmoschus eculentus Seed Extract Exhibits In Vitro and In Vivo Anti-Alzheimer's Potential Supported by Metabolomic and Computational Investigation

Abelmoschus esculentus Linn. (okra, F. Malvaceae) is a fruit widely consumed all over the world. In our study, the anti-Alzheimer's potential of A. esculentus was evaluated. An in vitro DPPH free radical assay on A. esculentus seed's total extract and AChE inhibition potential screening indicated a significant anti-Alzheimer's activity of the extract, which was confirmed through an in vivo study in an aluminum-intoxicated rat model. Additionally, in vivo results demonstrated significant improvement in Alzheimer's rats, which was confirmed by improving T-maze, beam balance tests, lower serum levels of AChE, norepinephrine, glycated end products, IL-6, and MDA. The levels of dopamine, BDNF, GSH, and TAC returned to normal values during the study. Moreover, histological investigations of brain tissue revealed that the destruction in collagen fiber nearly returns back to the normal pattern. Metabolomic analysis of the ethanolic extract of A. esculentus seeds via LC-HR-ESI-MS dereplicated ten compounds. A network pharmacology study displayed the relation between identified compounds and 136 genes, among which 84 genes related to Alzheimer's disorders, and focused on AChE, APP, BACE1, MAPT and TNF genes with interactions to all Alzheimer's disorders. Consequently, the results revealed in our study grant potential dietary elements for the management of Alzheimer's disorders.

Anti-Alzheimer activity of new coumarin-based derivatives targeting acetylcholinesterase inhibition

New 2-oxo-chromene-7-oxymethylene acetohydrazide derivatives 4a-d were designed and synthesized with a variety of bioactive chemical fragments. The newly synthesized compounds were evaluated as acetylcholinesterase (AChE) inhibitors and antioxidant agents in comparison to donepezil and ascorbic acid, respectively. Compound 4c exhibited a promising inhibitory impact with an IC₅₀ value of 0.802 μM and DPPH scavenging activity of 57.14 ± 2.77%. Furthermore, biochemical and haematological studies revealed that compound 4c had no effect on the blood profile, hepatic enzyme levels (AST, ALT, and ALP), or total urea in 4c-treated rats compared to the controls. Moreover, the histopathological studies of 4c-treated rats revealed the normal architecture of the hepatic lobules and renal parenchyma, as well as no histopathological damage in the examined hepatic, kidney, heart, and brain tissues. In addition, an in vivo study investigated the amelioration in the cognitive function of AD-rats treated with 4c through the T-maze and beam balance behavioural tests. Also, 4c detectably ameliorated MDA and GSH, reaching 90.64 and 27.17%, respectively, in comparison to the standard drug (90.64% and 35.03% for MDA and GSH, respectively). The molecular docking study exhibited a good fitting of compound 4c in the active site of the AChE enzyme and a promising safety profile. Compound 4c exhibited a promising anti-Alzheimer's disease efficiency compared to the standard drug donepezil.

Anti-Alzheimer Potential of a New (+)-Pinitol Glycoside Isolated from Tamarindus indica Pulp: In Vivo and In Silico Evaluations

Tamarindus indica Linn (tamarind, F. Leguminosae) is one of the most widely consumed edible fruits in the world. Phytochemical investigation of tamarind pulp n-butanol fraction yielded one new (+)-pinitol glycoside compound 1 (25% w/w), and 1D, 2D NMR, and HRESIMS investigation were used to confirm the new compound's structure. (+)-Pinitol glycoside showed anti-Alzheimer potential that was confirmed in prophylactic and treatment groups by decreasing time for the T-maze test; decreased TAO, brain and serum AChE, MDA, tau protein levels, and β amyloid peptide protein levels; and increasing GPX, SOD levels, and in vivo regression of the neurodegenerative features of Alzheimer's dementia in an aluminum-intoxicated rat model. The reported molecular targets for human Alzheimer's disease were then used in a network pharmacology investigation to examine their complex interactions and identify the key targets in the disease pathogenesis. An in silico-based analysis (molecular docking, binding free energy calculation (ΔG_Binding), and molecular dynamics simulation) was performed to identify the potential targets for compound 1. The findings of this study may lead to the development of dietary supplements for the treatment of Alzheimer's disease.

Integrative Genomic Analysis of m6a-SNPs Identifies Potential Functional Variants Associated with Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder that affects 35 million people worldwide. However, no potential therapeutics currently are available for AD because of the multiple factors involved in it, such as regulatory factors with their candidate genes, factors associated with the expression levels of its corresponding genes, and many others. To date, 29 novel loci from GWAS have been reported for AD by the Psychiatric Genomics Consortium (PGC2). Nevertheless, the main challenge of the post-GWAS era, namely to detect significant variants of the target disease, has not been conducted for AD. N6-methyladenosine (m6a) is reported as the most prevalent mRNA modification that exists in eukaryotes and that influences mRNA nuclear export, translation, splicing, and the stability of mRNA. Furthermore, studies have also reported m6a's association with neurogenesis and brain development. We carried out an integrative genomic analysis of AD variants from GWAS and m6a-SNPs from m6AVAR to identify the effects of m6a-SNPs on AD and identified the significant variants using the statistically significance value (p-value <0.05). The cis-regularity variants with their corresponding genes and their influence on gene expression in the gene expression profiles of AD patients were determined, and showed 1458 potential m6a-SNPs (based on p-value <0.05) associated with AD. eQTL analysis showed that 258 m6a-SNPs had cis-eQTL signals that overlapped with six significant differentially expressed genes based on p-value <0.05 in two datasets of AD gene expression profiles. A follow-up study to elucidate the impact of our identified m6a-SNPs in the experimental study would validate our findings for AD, which would contribute to the etiology of AD.

Antiamnesic Effects of Novel Phthalimide Derivatives in Scopolamine-Induced Memory Impairment in Mice: A Useful Therapy for Alzheimer's Disease

Phthalimides have diverse bioactivities and are attractive molecules for drug discovery and development. Here, we explored new synthesized phthalimide derivatives (compounds 1-3) in improving memory impairment associated with Alzheimer's disease (AD), using in vitro and ex vivo acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition and in vivo models, including Y-maze test and novel object recognition test (NORT). Compounds 1-3 exhibited significant AChE activity with IC₅₀ values of 10, 140, and 18 μM and BuChE with IC₅₀ values of 80, 50, and 11 μM, respectively. All compounds 1-3 showed excellent antioxidant potential in DPPH and ABTS assays with IC₅₀ values in the range of 105-340 and 205-350 μM, respectively. In ex vivo studies, compounds 1-3 also significantly inhibited both enzymes in a concentration-dependent manner along with significant antioxidant activities. In in vivo studies, compounds 1-3 reversed scopolamine-induced amnesia as indicated by a significant increase in the spontaneous alternation in the Y-maze test and an increase in the discrimination index in the NORT. Molecular docking was also conducted for compounds 1-3 against AChE and BuChE, which showed that compounds 1 and 3 have excellent binding with AChE and BuChE as compared to 2. These findings suggest that compounds 1-3 possess significant antiamnesic potential and may serve as useful leads to develop novel therapeutics for the symptomatic management and treatment of AD.

Para-Substituted Thiosemicarbazones as Cholinesterase Inhibitors: Synthesis, In Vitro Biological Evaluation, and In Silico Study

The current research reports the synthesis of 14 para-substituted thiosemicarbazone derivatives in good to excellent yields using standard procedures. Initially, 4-ethoxybenzaldehyde (1) and 4-nitrobenzaldehyde (2) were refluxed with thiosemicarbazide in the presence of acetic acid in ethanol for 4-5 h. Then, various substituted phenacyl bromides were treated with the desired thiosemicarbazones (3 and 4) in the presence of triethylamine in ethanol with constant stirring for 5-6 h. The resulting derivatives were confirmed through electron impact mass spectrometry and ¹H NMR spectroscopy and evaluated for anticholinesterase inhibitory activity. Among the series, four compounds, 19, 17, 7, and 6, showed potent inhibitory activity against the acetylcholinesterase (AChE) enzyme, having IC₅₀ values of 110.19 ± 2.32, 114.57 ± 0.15, 140.52 ± 0.11, and 160.04 ± 0.02 μM, respectively, compared with standard galantamine (IC₅₀ = 104.5 ± 1.20 μM). Similarly, compounds 19 (IC₅₀ = 145.11 ± 1.03 μM), 9 (IC₅₀ = 147.20 ± 0.09 μM), 17 (IC₅₀ = 150.36 ± 0.18 μM), and 6 (IC₅₀ = 190.21 ± 0.13 μM) were the most excellent inhibitors of butyrylcholinesterase (BChE) when compared with the standard drug galantamine (IC₅₀ = 156.8 ± 1.50 μM). In silico studies were accomplished on the produced derivatives in order to explain the binding interface of compounds with the active sites of AChE and BChE enzymes.

Scabicidal Potential of Coconut Seed Extract in Rabbits via Downregulating Inflammatory/Immune Cross Talk: A Comprehensive Phytochemical/GC-MS and In Silico Proof

Scabies is an invasive skin condition caused by Sarcoptes scabiei mites. The present study investigates the antiscabies potential of coconut seed extract (CSE) in rabbits. GC-MS analysis of the seed oil identified 17 known compounds, while CSE phytochemical investigation afforded 4 known ones. The topical application of seed extract improved all signs of infection, and the improvement started 3 days post application. However, in vitro application of the extract caused 99% mortality of mites 1 day post application. Histopathological examination revealed the absence of inflammatory infiltration and hyperkeratosis of the epidermis, compared with ivermectin-treated groups which revealed less improvement. The mRNA gene expression results revealed a suppression of IL-1β, IL-6, IL-10, MMP-9, VEGF, and MCP-1, and an upregulation of I-CAM-1, KGF as well as TIMP-1. The docking analysis emphasized a strong binding of gondoic acid with IL-1β, IL-6, and VEGF with high binding scores of -5.817, -5.291, and -8.362 kcal/mol, respectively, and a high binding affinity of 3″(1‴-O-β-D-glucopyranosyl)-sucrose with GST with -7.24 kcal/mol. Accordingly, and for the first time, our results highlighted the scabicidal potential of coconut seed extract, which opens the gate for an efficient, cost-effective as well as herbal-based alternative for the control of scabies in rabbits.

Comparative Metabolic Study of Tamarindus indica L.'s Various Organs Based on GC/MS Analysis, In Silico and In Vitro Anti-Inflammatory and Wound Healing Activities

The chemical composition of the n-hexane extract of Tamarindus indica's various organs-bark, leaves, seeds, and fruits (TIB, TIL, TIS, TIF)-was investigated using gas chromatography-mass spectrometry (GC/MS) analysis. A total of 113 metabolites were identified, accounting for 93.07, 83.17, 84.05, and 85.08 % of the total identified components in TIB, TIL, TIS, and TIF, respectively. Lupeol was the most predominant component in TIB and TIL, accounting for 23.61 and 22.78%, respectively. However, n-Docosanoic acid (10.49%) and methyl tricosanoate (7.09%) were present in a high percentage in TIS. However, α-terpinyl acetate (7.36%) and α-muurolene (7.52%) were the major components of TIF n-hexane extract. By applying a principal component analysis (PCA) and hierarchal cluster analysis (HCA) to GC/MS-based metabolites, a clear differentiation of Tamarindus indica organs was achieved. The anti-inflammatory activity was evaluated in vitro on lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. In addition, the wound healing potential for the n-hexane extract of various plant organs was assessed using the in-vitro wound scratch assay using Human Skin Fibroblast cells. The tested extracts showed considerable anti-inflammatory and wound-healing activities. At a concentration of 10 µg/mL, TIL showed the highest nitric oxide (NO) inhibition by 53.97 ± 5.89%. Regarding the wound healing potential, after 24 h, TIB, TIL, TIS, and TIF n-hexane extracts at 10 g/mL reduced the wound width to 1.09 ± 0.04, 1.12 ± 0.18, 1.09 ± 0.28, and 1.41 ± 0.35 mm, respectively, as compared to the control cells (1.37 ± 0.15 mm). These findings showed that the n-hexane extract of T. indica enhanced wound healing by promoting fibroblast migration. Additionally, a docking study was conducted to assess the major identified phytoconstituents' affinity for binding to glycogen synthase kinase 3-β (GSK3-β), matrix metalloproteinases-8 (MMP-8), and nitric oxide synthase (iNOS). Lupeol showed the most favourable binding affinity to GSK3-β and iNOS, equal to -12.5 and -13.7 Kcal/mol, respectively, while methyl tricosanoate showed the highest binding affinity with MMP-8 equal to -13.1 Kcal/mol. Accordingly, the n-hexane extract of T. indica's various organs can be considered a good candidate for the management of wound healing and inflammatory conditions.

The Protective and Therapeutic Anti-Alzheimer Potential of Olea europaea L. cv. Picual: An In Silico and In Vivo Study

LC-HRESIMS metabolomic profiling of Olea europaea L. cv. Picual (OEP) (Saudi Arabian olive cultivar, F. Oleacea) revealed 18 compounds. Using pharmacology networking to specify the targets of the identified compounds with a relationship to Alzheimer's disease, it was possible to identify the VEGFA, AChE, and DRD2 genes as the top correlated genes to Alzheimer's disease with 8, 8, and 6 interactions in the same order. The mechanism of action on cellular components, biological processes, and molecular functions was determined by gene enrichment analysis. A biological pathway comparison revealed 13 shared pathways between the identified genes and Alzheimer protein genes (beta-amyloid band tau proteins). The suggested extract's anti-Alzheimer potential in silico screening was confirmed through in vivo investigation in regressing the neurodegenerative features of Alzheimer's dementia in an aluminum-intoxicated rat model (protective and therapeutic effects, 100 mg/kg b.w.). In vivo results suggested that OEP extract significantly improved Alzheimer's rats, which was indicated by the crude extract's ability to improve T-maze performance; lower elevated serum levels of AChE, AB peptide, and Ph/T ratio; and normalize the reduced level of TAC during the study. The results presented in this study may provide potential dietary supplements for the management of Alzheimer's disease.

New Halogenated Compounds from Halimeda macroloba Seaweed with Potential Inhibitory Activity against Malaria

Malaria is one of the most important infectious diseases worldwide. The causative of the most severe forms of malaria, Plasmodium falciparum, has developed resistances against all the available antimalarial drugs. In the present study, the phytochemical investigation of the green seaweed Halimeda macroloba has afforded two new compounds 1–2, along with 4 known ones 3–6. The structures of the compounds had been confirmed using 1& 2D-NMR and HRESIMS analyses. Extensive machine-learning-supported virtual-screening suggested cytochrome-C enzyme as a potential target for compound 2. Docking, absolute-binding-free-energy (ΔG_binding) and molecular-dynamics-simulation (MDS) of compound 2 revealed the strong binding interaction of this compound with cytochrome-C. In vitro testing for crude extract and isolated compounds revealed the potential in vitro inhibitory activity of both extract and compound 2 against P. falciparum. The crude extract was able to inhibit the parasite growth with an IC₅₀ value of 1.8 ± 0.35 µg/mL. Compound 2 also showed good inhibitory activity with an IC₅₀ value of 3.2 ± 0.23 µg/mL. Meanwhile, compound 6 showed moderate inhibitory activity with an IC₅₀ value of 19.3 ± 0.51 µg/mL. Accordingly, the scaffold of compound 2 can be considered as a good lead compound for the future development of new antimalarial agents.

The Wound-Healing Potential of Olea europaea L. Cv. Arbequina Leaves Extract: An Integrated In Vitro, In Silico, and In Vivo Investigation

Olea europaea L. Cv. Arbequina (OEA) (Oleaceae) is an olive variety species that has received little attention. Besides our previous work for the chemical profiling of OEA leaves using LC−HRESIMS, an additional 23 compounds are identified. An excision wound model is used to measure wound healing action. Wounds are provided with OEA (2% w/v) or MEBO® cream (marketed treatment). The wound closure rate related to vehicle-treated wounds is significantly increased by OEA. Comparing to vehicle wound tissues, significant levels of TGF-β in OEA and MEBO® (p < 0.05) are displayed by gene expression patterns, with the most significant levels in OEA-treated wounds. Proinflammatory TNF-α and IL-1β levels are substantially reduced in OEA-treated wounds. The capability of several lignan-related compounds to interact with MMP-1 is revealed by extensive in silico investigation of the major OEA compounds (i.e., inverse docking, molecular dynamics simulation, and ΔG calculation), and their role in the wound-healing process is also characterized. The potential of OEA as a potent MMP-1 inhibitor is shown in subsequent in vitro testing (IC50 = 88.0 ± 0.1 nM). In conclusion, OEA is introduced as an interesting therapeutic candidate that can effectively manage wound healing because of its anti-inflammatory and antioxidant properties.