Investigations of In Vitro Anti-Acetylcholinesterase, Anti-Diabetic, Anti-Inflammatory, and Anti-Cancer Efficacy of Garden Cress (Lepidium sativum Linn.) Seed Extracts, as Well as In Vivo Biochemical and Hematological Assays

<b>Background/Objectives:</b> The current research was designed to quantify the active phyto-constituents and investigate the in vitro biological efficiency of different garden cress (<i>Lepidium sativum</i> Linn.) seed extracts against chronic diseases as well as the in vivo toxicities that may be induced in mice upon the administration of each extract at both studied therapeutic doses. <b>Methods</b>: The in vitro biological efficiency of different <i>L. sativum</i> extracts, such as methanolic, aqueous, acetone, and ethyl acetate extracts, was assessed. The inhibition percentage (%) and the median inhibitory concentration (IC₅₀) values of different <i>L. sativum</i> extracts were estimated against acetylcholinesterase enzyme, diabetes mellitus (α-amylase and α-glucosidase enzymes), and inflammation (cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and 5-lipoxygenase (5-LOX) enzymes). Additionally, the median inhibitory concentration (IC₅₀) values of different L. sativum extracts against HepG-2, Caco-2, and A549 cells were assessed using 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Moreover, the toxicities that might be induced in mice at hematological (using an automatic blood analyzer) and biochemical levels were evaluated. <b>Results:</b> It was found that the methanolic <i>L. sativum</i> extract possessed the highest in vitro biological activities compared to the other studied extracts. The inhibition percentage values of the methanolic extract were 51.34, 54.35, 44.10, 43.48, and 40.78% against acetylcholinesterase, α-amylase, α-glucosidase, protein denaturation, and proteinase enzymes, respectively. The methanolic extract also exhibited an inhibitory effect against the COX-1 (55.05%), COX-2 (57.30%), and 5-LOX (50.15%) enzymes. Additionally, the methanolic extract possesses the highest cytotoxic activity against HepG-2, Caco-2, and A549 cells, with IC₅₀ values of 52.27, 40.73, and 37.95 μg/mL, respectively. The median lethal doses (LD₅₀) showed that the methanolic extract was safer when administered orally, followed by aqueous and acetone, then ethyl acetate extract. It was found that methanolic, aqueous, and acetone extracts showed no alterations when administered orally at two studied doses (1/10 and 1/20 of LD₅₀) compared to the control. <b>Conclusions</b>: This study concluded that the methanolic extract possessed the highest in vitro biological activities and was safer than the other studied extracts, followed by aqueous, acetone, and then ethyl acetate extract. In the future, the in vivo biological efficacy of the methanolic <i>L. sativum</i> extract will be evaluated, as well as an elucidation of its mechanism against chronic diseases.