Synergistic Herb-Herb Interaction of the Antinociceptive and Anti-Inflammatory Effects of Syzygium aromaticum and Rosmarinus officinalis Combination.

The use of alternative medicine to treat pain has been increased, and the combination of several medicinal plants for its relief is a common practice in traditional medicine. The present study is aimed at determining whether a combination of Syzygium aromaticum (S. aromaticum) and Rosmarinus officinalis L. (R. officinalis) potentiates their antinociceptive and anti-inflammatory effects. These effects were explored using the formalin and carrageenan assays in rats, respectively. Animals received local pretreatment with S. aromaticum oil or R. officinalis ethanolic extract (0.1-100 µg/paw) alone or combined in a 1 : 1 rate. Concentration-response curves were built to compare pharmacological responses after an individual administration of S. aromaticum, R. officinalis, or their combination. The pharmacological interaction was investigated by an isobolographic study using the EC50 of each component in a fixed 1 : 1 ratio. S. aromaticum and R. officinalis administered alone showed significant and concentration-dependent antinociceptive and anti-inflammatory effects, but R. officinalis was more potent than S. aromaticum in both the antinociceptive and anti-inflammatory effects (EC50 = 7.96 ± 0.6 µg/paw vs. EC50 = 41.6 ± 1.7 µg/paw; EC50 = 1.97 ± 0.3 µg/paw vs. EC50 = 26.9 ± 2.5 µg/paw, respectively). The isobolographic analysis of the combination of these species in a 1 : 1 ratio showed a synergistic interaction between S. aromaticum and R. officinalis since Z mix (experimental value) was lower than Z add (theoretical value) for both the antinociceptive effect (Z mix = 0.45 ± 0.1 < Z add = 24.8 ± 1.3) and the anti-inflammatory effect (Z mix = 5.2 ± 0.6 < Z add = 14.4 ± 2.2), suggesting a potentiation for both pharmacological effects. These results prove evidence of the efficacy of mixture herb-herb used in folk medicine for pain therapy. It also emphasizes the requirement of pharmacological studies to explore the efficacy and safety of herb interactions.

Synergistic antinociceptive interaction of Syzygium aromaticum or Rosmarinus officinalis coadministered with ketorolac in rats.

Syzygium aromaticum (L.) Merr. & L.M. Perry (Mirtaceae) and Rosmarinus officinalis L. (Lamiaceae) are both medicinal plants used for centuries to alleviate pain. The aim of the study was to demonstrate the therapeutic potential utility of herb-drug association of S. aromaticum essential oil or R. officinalis ethanolic extract coadministered with ketorolac. Antinociceptive pharmacological interaction was investigated by an isbolographic study using the formalin test in rats. Both alone and in combination with ketorolac; S. aromaticum and R. officinalis produced a dose-dependent antinociceptive response. To plot the isobologram, we used the effective dose 50 of each one component in a fixed 1:1 ratio. The isobolographic analysis showed that, in both combinations, ketorolac plus essential oil S. aromaticum and ketorolac plus ethanolic extract R. officinalis, the experimental value (Zexp) was lower than the theoretical value (Zadd). In addition, this study shows that eugenol, a metabolite present in S. aromaticum, and ursolic acid, a metabolite present in R. officinalis, also synergized the antinociceptive effect of ketorolac. While, the oleanolic acid present in both medicinal species did not show a synergistic antinociceptive effect in combination with ketorolac. No adverse effects were observed with these herb-drug interactions. These findings suggest that essential oil S. aromaticum and ethanolic extract R. officinalis could be useful in combination with ketorolac for the treatment of inflammatory pain.

No effect of magnesium supplementation on metabolic control and insulin sensitivity in type 2 diabetic patients with normomagnesemia.

There are limited and conflicting data from clinical trials concerning the beneficial effects of magnesium supplementation on diabetic patients. We investigated the effects of magnesium supplementation on metabolic control and insulin sensitivity in type 2 diabetic patients with normomagnesemia. A total of 98 normomagnesemic subjects with type 2 diabetes were enrolled in a randomized, crossover, double-blind, placebo-controlled trial. Participants were randomly assigned to receive magnesium lactate (360 mg elemental magnesium) or placebo for three months, followed by a three-month washout period. Treatment assignments were then reversed over an additional three months of follow-up. The primary endpoint was a reduction in fasting glucose and HbA1c. A total of 56 subjects completed the follow-up in the magnesium and placebo supplementation groups. Urinary magnesium excretion was increased following magnesium supplementation in the intervention group compared with the placebo group (p = 0.0002). Fasting glucose, HbA1c, insulin and HOMA-IR, as well as lipid profile, did not change significantly during treatment. We concluded that magnesium supplementation does not improve metabolic control or insulin sensitivity in diabetic subjects with normomagnesemia.

Hypoglycemic effect of Carica papaya leaves in streptozotocin-induced diabetic rats.

BACKGROUND: Traditional plant treatment for diabetes has shown a surging interest in the last few decades. Therefore, the purpose of this study was to assess the hypoglycemic effect of the aqueous extract of C. papaya leaves in diabetic rats. Several studies have reported that some parts of the C. papaya plant exert hypoglycemic effects in both animals and humans. METHODS: Diabetes was induced in rats by intraperitoneal administration of 60 mg/kg of streptozotocin (STZ). The aqueous extract of C. papaya was administered in three different doses (0.75, 1.5 and 3 g/100 mL) as drinking water to both diabetic and non-diabetic animals during 4 weeks. RESULTS: The aqueous extract of Carica papaya (0.75 g and 1.5 g/100 mL) significantly decreased blood glucose levels (p<0.05) in diabetic rats. It also decreased cholesterol, triacylglycerol and amino-transferases blood levels. Low plasma insulin levels did not change after treatment in diabetic rats, but they significantly increased in non-diabetic animals. Pancreatic islet cells were normal in non-diabetic treated animals, whereas in diabetic treated rats, C. papaya could help islet regeneration manifested as preservation of cell size. In the liver of diabetic treated rats, C. papaya prevented hepatocyte disruption, as well as accumulation of glycogen and lipids. Finally, an antioxidant effect of C. papaya extract was also detected in diabetic rats. CONCLUSIONS: This study showed that the aqueous extract of C. papaya exerted a hypoglycemic and antioxidant effect; it also improved the lipid profile in diabetic rats. In addition, the leaf extract positively affected integrity and function of both liver and pancreas.