Mechanistic insights on burdock (Arctium lappa L.) extract effects on diabetes mellitus

The Systematic Assessment of the Membrane-Stabilizing and Antioxidant Activities of Several Kazakhstani Plants in the Asteraceae Family

The objective of our research was to examine the antioxidant and membrane-protective characteristics of a few medicinal plant extracts belonging to the Asteracea family, along with their flavonoid and polyphenolic content, in order to identify strategies for enhancing beverage composition and boosting the antioxidant capacity of green and black tea. The activity of aqueous-ethanolic extracts from the dried parts of plants, such as Arictum tomentosum Mill., Ghnapilum kasachstanicum Kirp. & Kuprian. ex Kirp., Artemisia schrenkiana Ledeb., A. rutifolia Steph. ex Spreng., A. cina O.Berg, and A. vulgaris L., were examined using a model of Wistar rats. Thiobarbituric acid-reacting substances (TBARS), a marker of malondialdehyde concentration, were used to measure the amount of lipid peroxidation (LPO) in liver microsomes. Considering the outcomes, the extracts from A. tomentosum, G. kasachstanicum, and A. vulgaris exhibit the strongest membrane-stabilizing action among those examined. At a concentration of 5 g/mL, the extracts of these plants demonstrated a significant anti-hemolitic impact, whereas the remaining extracts displayed a similar effect at doses above 10 g/mL. Accordingly, among the extracts studied, the A. tomentosum, G. kasachstanicum, A. schrenkiana, A. rutifolia, A. cina, and A. vulgaris extracts have significant antioxidant properties. The integrated antioxidant and antihemolytic qualities of A. tomentosum and green tea extracts were comparable to those of the individual plant extracts. When the extracts of A. schrenkiana and green tea were combined, similar outcomes were seen, suggesting that there was no appreciable synergistic interaction.

Amelioration of autophagy and inflammatory signaling pathways via α-lipoic acid, burdock and bee pollen versus lipopolysaccharide-induced insulin resistance in murine model

Lipopolysaccharide (LPS) has previously been implicated in insulin resistance by generating an innate immune response and activating inflammatory cascades. Many studies have discovered a relationship between high levels of serum LPS and the advancement of diabetic microvascular problems, indicating that LPS may play a role in the control of critical signaling pathways connected to insulin resistance. The current study focused on signaling pathways linked to insulin resistance and explored probable mechanisms of LPS-induced insulin resistance in a murine model. It next looked at the effects of burdock, bee pollen, and -lipoic acid on LPS-induced inflammation and autoimmune defects in rats. LPS intoxication was induced via ip injection for one week in a dose of 10 mg/kg followed by α-lipoic acid, Burdock and bee pollen in an oral treatment for one month. Following that, biochemical and molecular studies were performed. The RNA expression of the regulating genes STAT5A and PTEN was measured. In addition, ATF-4 and CHOP as autophagy biomarkers were also subjected to mRNA quantification. The results demonstrated a considerable improvement in the -lipoic acid, Burdock, and bee pollen treated groups via modifying oxidative stress indicators as well as molecular ones. Furthermore, glucose concentration in serum and α-amylase were also improved upon treatment with the superiority of α-lipoic acid for modulating all estimated parameters. In conclusion: the results declared in the current study suggested that α-lipoic acid could regulate insulin resistance signaling pathways induced by LPS intoxication.

Phytochemical Composition and Biological Activities of Arctium minus (Hill) Bernh.: A Potential Candidate as Antioxidant, Enzyme Inhibitor, and Cytotoxic Agent

Arctium minus (Hill) Bernh. (Asteraceae), which has a wide distribution area in Turkey, is a medicinally important plant. Eighty percent methanol extracts of the leaf, flower head, and root parts of A. minus were prepared and their sub-fractions were obtained. Spectrophotometric and chromatographic (high-performance liquid chromatography) techniques were used to assess the phytochemical composition. The extracts were evaluated for antioxidant activity by diphenyl-2-picrylhydrazil radical (DPPH^●), 2,2′-Azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS^●+) radical scavenging, and β-carotene linoleic acid bleaching assays. Furthermore, the extracts were subjected to α-amylase, α-glucosidase, lipoxygenase, and tyrosinase enzyme inhibition tests. The cytotoxic effects of extracts were investigated on MCF-7 and MDA-MB-231 breast cancer cell lines. The richest extract in terms of phenolic compounds was identified as the ethyl acetate sub-fraction of the root extract (364.37 ± 7.18 mg_GAE/g_extact). Furthermore, chlorogenic acid (8.855 ± 0.175%) and rutin (8.359 ± 0.125%) were identified as the primary components in the leaves’ ethyl acetate sub-fraction. According to all methods, it was observed that the extracts with the highest antioxidant activity were the flower and leaf ethyl acetate fractions. Additionally, ABTS radical scavenging activity of roots’ ethyl acetate sub-fraction (2.51 ± 0.09 mmol/L Trolox) was observed to be as effective as that of flower and leaf ethyl acetate fractions at 0.5 mg/mL. In the β-carotene linoleic acid bleaching assay, leaves’ methanol extract showed the highest antioxidant capacity (1422.47 ± 76.85) at 30 min. The enzyme activity data showed that α-glucosidase enzyme inhibition of leaf dichloromethane extract was moderately high, with an 87.12 ± 8.06% inhibition value. Lipoxygenase enzyme inhibition was weakly detected in all sub-fractions. Leaf methanol extract, leaf butanol, and root ethyl acetate sub-fractions showed 99% tyrosinase enzyme inhibition. Finally, it was discovered that dichloromethane extracts of leaves, roots, and flowers had high cytotoxic effects on the MDA-MB-231 cell line, with IC50 values of 21.39 ± 2.43, 13.41 ± 2.37, and 10.80 ± 1.26 µg/mL, respectively. The evaluation of the plant extracts in terms of several bioactivity tests revealed extremely positive outcomes. The data of this study, in which all parts of the plant were investigated in detail for the first time, offer promising results for future research.