No abstract

Several reports indicate anti-hyperglycemic effects of Syzygium aromaticum. In the present study, we report for the first time that clove extract (SAM) and its compound nigricin (NGC) decreases free fatty acid-mediated insulin resistance in mouse myoblasts. In addition, NGC was able to diminish insulin resistance in a diabetic mouse model. We observed that SAM and its compound NGC exhibited significant antioxidant activity in murine skeletal muscle cells. They also modulated stress signaling by reducing p38 MAP kinase phosphorylation. NGC and SAM treatments enhanced proximal insulin signaling by decreasing serine phosphorylation of insulin receptor substrate-1 (IRS-1) and increasing its tyrosine phosphorylation. SAM and NGC treatments also modified distal insulin signaling by enhancing protein kinase B (PKB) and glycogen synthase kinase-3-beta (GSK-3 beta) phosphorylation in muscle cells. Glucose uptake was enhanced in muscle cells after treatment with SAM and NGC. We observed increased glucose tolerance, glucose-stimulated insulin secretion, decreased insulin resistance, and increased beta cell function in diabetic mice treated with NGC. The results of our study demonstrate that clove extract and its active agent NGC can be potential therapeutic agents for alleviating insulin resistance.

Syzygium aromaticum (Myrtaceae) flower buds (clove) are traditionally known to possess antimicrobial, antiprotozoal, antiviral and other activities, including the antinociceptive action. Scientific evidence also suggests the antileishmanial, antiherpetic and anti-HIV activities of the buds. This paper reports the antinociceptive activity of S. aromaticum flower buds, reinforcing its use in decreasing the pain. The present study was designed to confirm the analgesic activity of S. aromaticum extract and seven of its fractions to reveal the common belief in its painkilling effects. We chose two thermal nociception assays (i) hot–plate test (ii) and tail-flick method as our experimental techniques. Both of these methods are well established to screen anti-nociceptive activities in new molecules. The standard drug indomethacin (5 mg/kg) given by intra-peritoneal route was used in the study for comparison. The study has shown that the methanolic extract (SA-EXT) and its active fractions possess anti-nociceptive activity (pandlt;0.05) in the models of nociception used.

In the present study oleanolic acid and its derivatives were studied for their in-vivo nematicidal activity against root knot nematode (RKN) Meloidogyne incognita. A series of C-28-oleanolates including five new (5, 7-10) and seven known (1-4, 6, 11-12) compounds were synthesized and their nematicidal activity was determined and compared with the standard nematicide furadan for the first time. The structures of the compounds were elucidated through 1H NMR, 13C NMR and EIMS. Compounds 4, 5, 7 , 8 and 10 showed ~ 90% inhibition of RKN at 0.125% concentration after 72 hours showing their potential use in nematicidal control.