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991.
Garlic’s main bioactive organosulfur component, diallyl trisulfide (DATS), has been widely investigated in cancer models. However, DATS is not suitable for clinical use due to its low solubility. The current study seeks to improve DATS bioavailability and assess its chemopreventive and chemosensitizing properties in an AOM-induced colorectal cancer model. The polyethylene glycol coated Distearoylphosphatidylcholine/Cholesterol (DSPC/Chol) comprising DATS-loaded DATSL and doxorubicin (DOXO)-encapsulated DOXL liposomes was prepared and characterized. The changes in the sensitivity of DATS and DOXO by DATSL and DOXL were evaluated in RKO and HT-29 colon cancer cells. The synergistic effect of DATSL and DOXL was studied by cell proliferation assay in the combinations of IC10, IC25, and IC35 of DATSL with the IC10 of DOXL. AOM, DATSL, and DOXL were administered to different groups of mice for a period of 21 weeks. The data exhibited ~93% and ~46% entrapment efficiency of DATSL and DOXL, respectively. The size of sham liposomes was 110.5 nm, whereas DATSL and DOXL were 135.5 nm and 169 nm, respectively. DATSL and DOXL exhibited significant sensitivity in the cell proliferation experiment, lowering their IC50 doses by more than 8- and 14-fold, respectively. However, the DATSL IC10, IC25, and IC35 showed escalating chemosensitivity, and treated the cells in combination with DOXL IC10. Analysis of histopathological, cancer marker enzymes, and antioxidant enzymes revealed that the high dose of DATSL pretreatment and DOXL chemotherapy is highly effective in inhibiting AOM-induced colon cancer promotion. The combination of DATSL and DOXL indicated promise as a colorectal cancer treatment in this study. Intermolecular interactions of DATS and DOXO against numerous cancer targets by molecular docking indicated MMP-9 as the most favourable target for DATS exhibiting binding energy of −4.6 kcal/mol. So far, this is the first research to demonstrate the chemopreventive as well as chemosensitizing potential of DATSL in an animal model of colorectal cancer.  相似文献   
992.
The interaction between erlotinib (ERL) and bovine serum albumin (BSA) was studied in the presence of quercetin (QUR), a flavonoid with antioxidant properties. Ligands bind to the transport protein BSA resulting in competition between different ligands and displacing a bound ligand, resulting in higher plasma concentrations. Therefore, various spectroscopic experiments were conducted in addition to in silico studies to evaluate the interaction behavior of the BSA-ERL system in the presence and absence of QUR. The quenching curve and binding constants values suggest competition between QUR and ERL to bind to BSA. The binding constant for the BSA-ERL system decreased from 2.07 × 104 to 0.02 × 102 in the presence of QUR. The interaction of ERL with BSA at Site II is ruled out based on the site marker studies. The suggested Site on BSA for interaction with ERL is Site I. Stability of the BSA-ERL system was established with molecular dynamic simulation studies for both Site I and Site III interaction. In addition, the analysis can significantly help evaluate the effect of various quercetin-containing foods and supplements during the ERL-treatment regimen. In vitro binding evaluation provides a cheaper alternative approach to investigate ligand-protein interaction before clinical studies.  相似文献   
993.
For most researchers, discovering new anticancer drugs to avoid the adverse effects of current ones, to improve therapeutic benefits and to reduce resistance is essential. Because the COX-2 enzyme plays an important role in various types of cancer leading to malignancy enhancement, inhibition of apoptosis, and tumor-cell metastasis, an indispensable objective is to design new scaffolds or drugs that possess combined action or dual effect, such as kinase and COX-2 inhibition. The start compounds A1 to A6 were prepared through the diazo coupling of 3-aminoacetophenone with a corresponding phenol and then condensed with two new chalcone series, C7–18. The newly synthesized compounds were assessed against both COX-2 and epidermal growth factor receptor (EGFR) for their inhibitory effect. All novel compounds were screened for cytotoxicity against five cancer cell lines. Compounds C9 and G10 exhibited potent EGFR inhibition with IC50 values of 0.8 and 1.1 µM, respectively. Additionally, they also displayed great COX-2 inhibition with IC50 values of 1.27 and 1.88 µM, respectively. Furthermore, the target compounds were assessed for their cytotoxicity against pancreatic ductal cancer (Panc-1), lung cancer (H-460), human colon cancer (HT-29), human malignant melanoma (A375) and pancreatic cancer (PaCa-2) cell lines. Interestingly, compounds C10 and G12 exhibited the strongest cytotoxic effect against PaCa-2 with average IC50 values of 0.9 and 0.8 µM, respectively. To understand the possible binding modes of the compounds under investigation with the receptor cites of EGFR and COX-2, a virtual docking study was conducted.  相似文献   
994.
Acacia seyal is an important source of gum Arabic. The availability, traditional, medicinal, pharmaceutical, nutritional, and cosmetic applications of gum acacia have pronounced its high economic value and attracted global attention. In addition to summarizing the inventions/patents applications related to gum A. seyal, the present review highlights recent updates regarding its phytoconstituents. Traditional, cosmetic, pharmaceutical, and medicinal uses with the possible mechanism of actions have been also reviewed. The patent search revealed the identification of 30 patents/patent applications of A. seyal. The first patent related to A. seyal was published in 1892, which was related to its use in the prophylaxis/treatment of kidney and bladder affections. The use of A. seyal to treat cancer and osteoporosis has also been patented. Some inventions provided compositions and formulations containing A. seyal or its ingredients for pharmaceutical and medical applications. The inventions related to agricultural applications, food industry, cosmetics, quality control of gum Arabic, and isolation of some chemical constituents (L-rhamnose and arabinose) from A. seyal have also been summarized. The identification of only 30 patents/patent applications from 1892 to 15 November 2021 indicates a steadily growing interest and encourages developing more inventions related to A. seyal. The authors recommend exploring these opportunities for the benefit of society.  相似文献   
995.
Excessive storage of lipids in visceral or ectopic sites stimulates adipokine production, which attracts macrophages. This process determines the pro- and anti-inflammatory response regulation in adipose tissue during obesity-associated systemic inflammation. The present study aimed to identify the composition of Ocimum basilicum L. (basil) seed extract and to determine its bio-efficacy on adipocyte thermogenesis or fatty acid oxidation and inhibition of lipid accumulation and adipokine secretion. Ocimum basilicum L. seed methanol extract (BSME) was utilized to analyze the cytotoxicity vs. control; lipid accumulation assay (oil red O and Nile red staining), adipogenesis and mitochondrial-thermogenesis-related gene expression vs. vehicle control were analyzed by PCR assay. In addition, vehicle control and BSME-treated adipocytes condition media were collected and treated with lipopolysaccharide (LPS)-induced macrophage to identify the macrophage polarization. The results shown that the active components present in BSME did not produce significant cytotoxicity in preadipocytes or macrophages in the MTT assay. Furthermore, oil red O and Nile red staining assay confirmed that 80 and 160 μg/dL concentrations of BSME effectively arrested lipid accumulation and inhibited adipocyte maturation, when compared with tea polyphenols. Gene expression level of adipocyte hyperplasia (CEBPα, PPARγ) and lipogenesis (LPL)-related genes have been significantly (p ≤ 0.05) downregulated, and mitochondrial-thermogenesis-associated genes (PPARγc1α, UCP-1, prdm16) have been significantly (p ≤ 0.001) upregulated. The BSME-treated, maturing, adipocyte-secreted proteins were detected with a decreased protein level of leptin, TNF-α, IL-6 and STAT-6, which are associated with insulin resistance and macrophage recruitment. The “LPS-stimulated macrophage” treated with “BSME-treated adipocytes condition media”, shown with significant (p ≤ 0.001) decrease in metabolic-inflammation-related proteins—such as PGE-2, MCP-1, TNF-α and NF-κB—were majorly associated with the development of foam cell formation and progression of atherosclerotic lesion. The present findings concluded that the availability of active principles in basil seed effectively inhibit adipocyte hypertrophy, macrophage polarization, and the inflammation associated with insulin resistance and thrombosis development. Ocimum basilicum L. seed may be useful as a dietary supplement to enhance fatty acid oxidation, which aids in overcoming metabolic complications.  相似文献   
996.
The present study involves the integrated network pharmacology and phytoinformatics-based investigation of phytocompounds from Ocimum tenuiflorum against diabetes mellitus-linked Alzheimer’s disease. It aims to investigate the mechanism of the Ocimum tenuiflorum phytocompounds in the amelioration of diabetes mellitus-linked Alzheimer’s disease through network pharmacology, druglikeness and pharmacokinetics, molecular docking simulations, GO analysis, molecular dynamics simulations, and binding free energy analyses. A total of 14 predicted genes of the 26 orally bioactive compounds were identified. Among these 14 genes, GAPDH and AKT1 were the most significant. The network analysis revealed the AGE-RAGE signaling pathway to be a prominent pathway linked to GAPDH with 50.53% probability. Upon the molecular docking simulation with GAPDH, isoeugenol was found to possess the most significant binding affinity (−6.0 kcal/mol). The molecular dynamics simulation and binding free energy calculation results also predicted that isoeugenol forms a stable protein–ligand complex with GAPDH, where the phytocompound is predicted to chiefly use van der Waal’s binding energy (−159.277 kj/mol). On the basis of these results, it can be concluded that isoeugenol from Ocimum tenuiflorum could be taken for further in vitro and in vivo analysis, targeting GAPDH inhibition for the amelioration of diabetes mellitus-linked Alzheimer’s disease.  相似文献   
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