Network pharmacology and experimental insights into STAT3 inhibition by novel isoxazole derivatives of piperic acid in triple negative breast cancer

STAT3 is a crucial member within a family of seven essential transcription factors. Elevated STAT3 levels have been identified in various cancer types, notably in breast cancer (BC). Consequently, inhibiting STAT3 is recognized as a promising and effective strategy for therapeutic intervention against breast cancer. We herein synthesize a library of isoxazole (PAIs) from piperic acid [2E, 4E)-5-(2H-1,3-Benzodioxol-5-yl) penta-2,4-dienoic acid] on treatment with propargyl bromide followed by oxime under prescribed reaction conditions. Piperic acid was obtained by hydrolysis of piperine extracted from Piper nigrum. First, we checked the binding potential of isoxazole derivatives with breast cancer target proteins by network pharmacology, molecular docking, molecular dynamic (MD) simulation and cytotoxicity analysis as potential anti-breast cancer (BC) agents. The multi-source databases were used to identify possible targets for isoxazole derivatives. A network of protein-protein interactions (PPIs) was generated by obtaining 877 target genes that overlapped gene symbols associated with isoxazole derivatives and BC. Molecular docking and MD modelling demonstrated a strong affinity between isoxazole derivatives and essential target genes. Further, the cell viability studies of isoxazole derivatives on the human breast carcinoma cell lines showed toxicity in all breast cancer cell lines. In summary, our study indicated that the isoxazole derivative showed the significant anticancer activity. The results highlight the prospective utility of isoxazole derivatives as new drug candidates for anticancer chemotherapy, suggesting route for the continued exploration and development of drugs suitable for clinical applications.

Extraction, isolation, synthesis, and biological evaluation of novel piperic acid derivatives for the treatment of Alzheimer's disease

In this paper, we developed a series of piperic acid (PA) analogs with the aim of overcoming the limitations associated with the natural products for the management of Alzheimer's disease (AD). A comprehensive SAR study was performed to enhance cholinesterase inhibition of PA. The acetylcholinesterase inhibition and its kinetic data suggested 6j as the lead molecule (AChE IC₅₀ = 2.13 ± 0.015 µM, BChE = 28.19 ± 0.20%), in comparison to PA (AChE = 7.14 ± 0.98%) which was further selected for various biological studies in AD models. 6j, exhibited interaction with the peripheral anionic site of AChE, BBB permeability (Pe = 7.98), and antioxidant property (% radical scavenging activity = 35.41 ± 1.09, 2.43 ± 1.65, for 6j and PA at 20 M[Formula: see text], respectively). The result from the metal chelation study suggests that 6j did not effectively chelate iron. The molecular modeling studies suggested that 6j could effectively interact with Ser293, Phe295, Arg296, and Tyr34 of AChE. In the cell-based cytotoxicity studies, 6j exhibited cytocompatibility at the different tested concentrations. The acute toxicity data on mice suggested that compound 6j had no renal and hepatotoxicity at 500 mg/kg. Moreover, 6j could effectively reverse scopolamine-induced amnesia by improving spatial and cognitive memory in mice. The above results strongly suggest that compound 6j may act as a novel multi-targeted lead for AD therapy.

Preparation and characterization of polyvinyl alcohol-piperic acid composite film for potential food packaging applications

Piperic acid, a natural product-based derivative, has been used with polyvinyl alcohol for the first time to form polymer composite films for its suitable modification in physicochemical and antimicrobial properties. Initially, piperic acid was synthesized from piperine, a natural alkaloid extracted from black pepper (Piper nigrum). The solvent casting method was used for the synthesis of PVA-piperic acid composite films. The films were characterized by various spectral and microscopic techniques like UV-visible spectroscopy, FT-IR, SEM, XRD, and TGA. The antibacterial activity was shown by these polymer composites of piperic acid against Gram-positive Staphylococcus aureus (S. aureus-ATCC8738P) and Gram-negative Escherichia coli (E. coli-ATCC8739) was worthwhile. The antifungal activity of the composite films was evaluated by the food poisoning technique. Percentage mycelial growth inhibition was found maximum against Fusarium solani than Aspergillus and Penicillium. The water vapour and oxygen barrier properties are enhanced with the incorporation of increased content of piperic acid. Also, enhancement in the tensile strength of PVA/PA composite film was observed, while elongation at break shows decreased trend with the addition of piperic acid. The surface properties of polymer composite films were determined by contact angle measurements. Contact angle shows a considerable increase in these films when compared to virgin PVA film. It was increased by 56.1° in 15 mL composite film containing a higher concentration of piperic acid than virgin PVA.

Natural inspired piperine-based sulfonamides and carboxylic acids as carbonic anhydrase inhibitors: Design, synthesis and biological evaluation

The natural product piperine, the major bioactive alkaloid present in black pepper fruits, has the ability to modulate the functional activity of several biological targets. In this study, we have utilized the natural piperine as a tail moiety to develop new SLC-0111 analogues (6a-d, 8 and 9) as potential carbonic anhydrase inhibitors. Thereafter, different functionalities, free carboxylic acid (11a-c), acetyl (13a) and ethyl ester (13b-c), were exploited as bioisosteres of the sulfamoyl functionality. All piperine-based derivatives were assessed for their inhibitory actions against four human (h) CA isoforms: hCA I, II, IX and XII. The best hCA inhibitory activity was observed for the synthesized primary piperine-sulfonamides (6a-d and 8). In particular, both para-regioisomers (6c and 8) emerged as the most potent hCA inhibitors in this study with two-digit nanomolar activity against hCA II (K_Is = 93.4 and 88.6 nM, respectively), hCA IX (K_Is = 38.7 and 68.2 nM, respectively), and hCA XII (K_Is = 57.5 and 45.6 nM, respectively). Moreover, piperine-sulfonamide 6c was examined for its anti-cancer and pro-apoptotic actions towards breast MCF-7 cancer cell line. Collectively, piperine-based sulfonamides could be considered as a promising scaffold for development of efficient anticancer candidates with potent CA inhibitory activities.

Evaluation of the antinociceptive and anti-inflammatory activities of piperic acid: Involvement of the cholinergic and vanilloid systems

Piperin is the active compound of black pepper (Piper nigrum). From the piperine was obtained the molecule of the piperic acid (PAC). The objective of this study was to evaluate the antinociceptive and anti-inflammatory of the compound. The antinociceptive effects of PAC were evaluated by abdominal writhing, formalin, capsaicin and tail-flick tests; while the anti-inflammatory effects were evaluated by paw oedema and air pouch tests, and in vitro COX inhibition assay. The possible action mechanism of PAC was evaluated using naloxone, L-NAME, glibenclamide and atropine in tail flick test and by Cholinesterase activity assay and production of TNF-α and IL-1β. PAC significantly reduced the nociceptive effects induced by acetic acid or formalin in mice. PAC also demonstrated an antinociceptive effect in the tail-flick model. The muscarinic receptor antagonist, atropine reduced the antinociceptive effect of PAC in the tail-flick model. PAC was able to inhibit capsaicin-induced nociception, showing involvement of TRPV1. The compound did not alter the motor capacity of the animals, not interfering in the nociceptive response. PAC also showed anti- inflammatory activity by inhibiting the formation of carrageenan-induced paw oedema, leukocyte migration, and cytokine production / release. Atropine reduced the activity of PAC on leukocyte migration, and cytokine production. The compound showed to be able to reduce the cytokine production stimulated by capsaicin. PAC inhibited the COX activity. The results presented suggest that the possible cholinomimetic action and vanilloid agonist of the piperic acid may be responsible by antinociceptive and anti- inflammatory effects; these effects are devoid of toxicity.