Synergistic Antinociceptive Effect of β-Caryophyllene Oxide in Combination with Paracetamol, and the Corresponding Gastroprotective Activity

Pain is the most frequent symptom of disease. In treating pain, a lower incidence of adverse effects is found for paracetamol versus other non-steroidal anti-inflammatory drugs. Nevertheless, paracetamol can trigger side effects when taken regularly. Combined therapy is a common way of lowering the dose of a drug and thus of reducing adverse reactions. Since β-caryophyllene oxide (a natural bicyclic sesquiterpene) is known to produce an analgesic effect, this study aimed to determine the anti-nociceptive and gastroprotective activity of administering the combination of paracetamol plus β-caryophyllene oxide to CD1 mice. Anti-nociception was evaluated with the formalin model and gastroprotection with the model of ethanol-induced gastric lesions. According to the isobolographic analysis, the anti-nociceptive interaction of paracetamol and β-caryophyllene oxide was synergistic. Various pain-related pathways were explored for their possible participation in the mechanism of action of the anti-nociceptive effect of β-caryophyllene oxide, finding that NO, opioid receptors, serotonin receptors, and K+ATP channels are not involved. The combined treatment showed gastroprotective activity against ethanol-induced gastric damage. Hence, the synergistic anti-nociceptive effect of combining paracetamol with β-caryophyllene oxide could be advantageous for the management of inflammatory pain, and the gastroprotective activity should help to protect against the adverse effects of chronic use.

Molecular docking and anti-ulcerative potential of Cucumis (L. Inodorous) on ibuprofen induced gastric ulceration in male wistar animals

BACKGROUND

The use of NSAIDs have caused stomach injury by inhibiting endogenous mucosal prostaglandin production. Cucumis melo is reported to possess antiulcer potential. This study investigates the mechanism underlying the antiulcer potentials of Cucumis melo (CUM).

METHODS

Thirty-five male Wistar rat were randomly assigned to each of seven groups; A(control given water and rat pellets), B(gastric ulcer induced with ibuprofen 400 mg/kg), C (Misoprotol 200 μg/kg), D to G (pretreated with different variation of CUM extract; 25 %, 50 %, 75 % and 100 % at a dose of 1 ml/kg for 3 weeks prior to gastric ulcer induction). Ulcer score, ulcer index and percentage inhibition, total gastric acidity was measured. Antioxidant activities, Malondialdehyde, H⁺/K⁺ ATPase, PGE2, TNF-α was done by spectrophotometry. Molecular docking investigation of Cucumis melo compounds against Prostaglandin E2 was carried out. Level of significance was tested at P ≤ 0.05 using Tukey post hoc.

RESULT

Total gastric acidity, ulcer score, ulcer index, MDA, TNF-α significantly decreased after CUM treatment when compared to group B. The percentage inhibition, antioxidant activities, PGE2 concentration was significantly increased in all treatment groups compared to group B. Interactions of selected compounds of CUM with Prostaglandin E2 at various docking pockets showed folic acid has highest binding affinity followed by delta7-avenasterol and codisterol to PGE2 receptor. this study shows that one of the mechanisms by which CUM exhibits its antiulcer potential by enhancing Prostaglandin synthesis and antioxidant capacity. Therefore, Cucumis melo can therefore be explored as novel antiulcer agents.

Ethenzamide Exerts Protective Effects against Ibuprofen-Induced Gastric Mucosal Damage in Rats by Suppressing Gastric Contraction

Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to cause gastric mucosal damage, in which gastric hypermotility has been reported to play a primary role. The antipyretic analgesic drug ethenzamide (ETZ) is widely used in combination with other NSAIDs and, in a recent study, was found to possess 5-hydroxytriptamine (5HT)2B receptor antagonistic activity. Therefore, the inhibition of gastric contraction via 5HT2B receptor blockade by ETZ might contribute to ETZ's protective effect against NSAIDs-induced gastric mucosal damage. In the present study, we examined the effects of ETZ on gastric contraction and ibuprofen (IBP)-induced gastric mucosal damage in rats. We found that ETZ suppressed both 5HT- and α-methyl-5HT (5HT2 receptor agonist)-induced contractions of rat-isolated gastric fundus in a concentration-dependent manner. This suppressive effect of ETZ was not seen for either high-KCl- or acetylcholine-induced contractions. Furthermore, ETZ was confirmed to decrease ibuprofen-induced gastric mucosal damage in a dose-dependent manner in rats. Similarly, clonidine is known to reduce gastric motility, and methysergide (a 5HT2 receptor antagonist) is known to inhibit 5HT-induced contractions of the gastric fundus, which also decreases IBP-induced gastric mucosal damage, respectively. Although further research on other possible sites or mechanisms of action would be needed, these results suggest that ETZ exerts a protective effect against IBP-induced gastric mucosal damage and that suppressing the gastric contraction may play an important role in the gastroprotective effect of ETZ.

Ethnopharmacological Inspections of Organic Extract of Oroxylum indicum in Rat Models: A Promising Natural Gift

The stem bark of Oroxylum indicum (O. indicum) was aimed at testing for anti-inflammatory, antiulcerative, antihyperglycemic, and antidyslipidemic activities. Liver enzyme concentration (SGPT, SGOT) had also been assessed. After being extracted in organic solvent, 3 distinct doses, 100, 200, and 400 mg/kg b.w. (p.o.), were used. For edema formation 0.1 ml carrageenan at a dose of 1% w/v was injected into paw of left hind. It showed a fall of edemas 37.50%, 48.34%, and 55.83% while used doses were 100, 200, and 400 mg/kg b.w. (p.o.) individually. The EtOH extract of O. indicum (50%) and its fractions PET, CLF, EtOAc, and nBUT were studied against ethanol-induced gastric mucosal damage. Only PET and n-BuOH exhibited the highest percentage of protection and were 96% and 99%, respectively, persuaded by ethanol. In OGTT glibenclamide revealed reduction of glucose level to 7.55 ± 0.22 mmol/L from 10.57 ± 0.32 mmol/L after 30 minutes. Antihyperglycemic activities were assessed for 8- and 12-week duration in diabetic rats. Glibenclamide reduced glucose level from 33.50±0.31 to 7.90±0.19 mmol/L in 12 weeks. In 12 and 8 weeks, combination therapy lowered blood glucose level to a normal extent by 79% and 61% individually. In antidyslipidemic activities after 12-week treatment, it revealed simvastatin; MEOI (400 mg/kg b.w.) and combination of both reduced TC level by 44%, 28%, and 48% consequently followed by TG and LDL. In 8-week treatment, HDL levels were increased by 34%, 13%, and 36%, and in 12 weeks increased by 36%, 8%, and 38% consequently. Liver enzyme concentration after 12 weeks of treatment with glibenclamide, 400 mg/kg b.w. (p.o.) of MEOI and combination of both, exhibited the fact that concentration of SGPT showed downturn by 43.23%, 8.01%, and 54.86% and SGOT by 42.40%, 5.31%, and 44.85%. This study remarked that O. indicum has anti-inflammatory, antiulcer, antidiabetic, and antidyslipidemic potentials but has no ameliorative effect on liver enzyme.

Involvement of Extracellular Signal-Regulated Kinase 5 in Kinin B1 Receptor Upregulation in Isolated Human Umbilical Veins

The upregulated kinin B1 receptors exert a pivotal role in modulating inflammatory processes. In isolated human umbilical veins (HUVs), kinin B1 receptor is upregulated as a function of in vitro incubation time and proinflammatory stimuli. The aim of this study was to evaluate, using functional and biochemical methods, the involvement of extracellular signal-regulated kinase 5 (ERK5), p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase 1/2 (ERK1/2) on the kinin B1 receptor upregulation process in HUV. Real-time polymerase chain reaction analysis revealed for the first time that kinin B1 receptor mRNA expression closely parallels the functional sensitization to kinin B1 receptor selective agonist des-Arg(10)-kallidin (DAKD) in HUV. Moreover, the selective inhibition of ERK5, p38 MAPK, and JNK, but not ERK1/2, produced a dose-dependent rightward shift of the concentration-response curves to DAKD after 5-hour incubation and a reduction in kinin B1 receptor mRNA expression. Biochemical analyses showed that ERK5, p38 MAPK, and JNK phosphorylation is maximal during the first 2 hours postisolation, followed by a significant reduction in the last 3 hours. None of the treatments modified the responses to serotonin, an unrelated agonist, suggesting a specific effect on kinin B1 receptor upregulation. The present work provides for the first time pharmacologic evidence indicating that ERK5 plays a significant role on kinin B1 receptor upregulation. Furthermore, we confirm the relevance of p38 MAPK and JNK as well as the lack of effect of ERK1/2 in this process. This study may contribute to a better understanding of MAPK involvement in inflammatory and immunologic diseases.