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Mechanisms of gastroprotection of methanol extract of Melastoma malabathricum leaves.

Zakaria ZA, Balan T, Mamat SS, Mohtarrudin N, Kek TL, Salleh MZ - BMC Complement Altern Med (2015)

Bottom Line: The involvement of endogenous nitric oxide (NO) and sulfhydryl (SH) compounds in the gastroprotective effect of MEMM were also measured.MEMM inhibited the lipoxygenase (LOX) and xanthine oxidase (XO) activities with the highest affinity for the former while quercitrin showed high affinity for XO activity.MEMM exhibited a gastroprotective activity due partly to the presence of quercitrin, its antioxidant and anti-inflammatory activities, and via the modulation of NO and SH groups.

View Article: PubMed Central - PubMed

Affiliation: Halal Product Research Institute, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia. dr_zaz@yahoo.com.

ABSTRACT

Background: Melastoma malabathricum L. (Melastomaceae) is a small shrub with various medicinal uses. The present study was carried out to determine the gastroprotective mechanisms of methanol extract of M. malabathricum leaves (MEMM) in rats.

Methods: The extract's mechanisms of gastroprotection (50, 250, 500 mg/kg) were studied using the pylorus-ligation in rat model wherein volume, pH, free and total acidity of gastric juice, and gastric wall mucus content were determined. The involvement of endogenous nitric oxide (NO) and sulfhydryl (SH) compounds in the gastroprotective effect of MEMM were also measured. MEMM was subjected to the antioxidant, anti-inflammatory and phytochemical analysis and HPLC profiling.

Results: MEMM contained various phyto-constituents with quercitrin being identified as part of them. MEMM and quercitrin: i) significantly (p < 0.05) reduced the volume and acidity of gastric juice while increasing the pH and gastric wall mucus content.; ii) significantly (p < 0.05) increased the level of SOD, GTP and GTR while significantly (p < 0.05) reduced the level of CAT, MPO and TBARS activities.; iii) exerted gastroprotective activity when assessed using the ethanol-induced gastric ulcer assay, which was reversed by N(G)-nitro-L-arginine methyl esters (L-NAME; an inhibitor of NO synthase) and N-ethylmaleimide (NEM; a sulfhydryl (SH) blocker). MEMM inhibited the lipoxygenase (LOX) and xanthine oxidase (XO) activities with the highest affinity for the former while quercitrin showed high affinity for XO activity.

Conclusions: MEMM exhibited a gastroprotective activity due partly to the presence of quercitrin, its antioxidant and anti-inflammatory activities, and via the modulation of NO and SH groups.

No MeSH data available.


Related in: MedlinePlus

Effect of MEMM on the nitric oxide (NO) production and RAW 264.7 cells’ viability. The assays were done in triplicate. One way ANOVA was followed by Dunnett’s post hoc test, *p < 0.05 shows significant difference as compared to the IFN-γ/LPS-treated group (inflammation induced group). 200 μM L-NAME.
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Fig3: Effect of MEMM on the nitric oxide (NO) production and RAW 264.7 cells’ viability. The assays were done in triplicate. One way ANOVA was followed by Dunnett’s post hoc test, *p < 0.05 shows significant difference as compared to the IFN-γ/LPS-treated group (inflammation induced group). 200 μM L-NAME.

Mentions: The in vitro effect of MEMM (12.5-100 μg/ml) on percentage of RAW 264.7 cell viability and NO production determined using the MTT assay is shown in Figure 3. The results showed that the MEMM, at all concentrations, did not affect cell viability. The extract was found to significantly (p < 0.05) increased the percentage of inhibition of NO production in LPS-induced RAW 264.7 cells. The amount of nitrite, a stable metabolite of NO, was used as the indicator of NO production in the medium. L-NAME, a standard NOS inhibitor, caused a significant inhibition of NO (p < 0.05). Quercitrin, on the other hand, also did not affect cell viability but caused significant (p < 0.05) inhibition of NO production.Figure 3


Mechanisms of gastroprotection of methanol extract of Melastoma malabathricum leaves.

Zakaria ZA, Balan T, Mamat SS, Mohtarrudin N, Kek TL, Salleh MZ - BMC Complement Altern Med (2015)

Effect of MEMM on the nitric oxide (NO) production and RAW 264.7 cells’ viability. The assays were done in triplicate. One way ANOVA was followed by Dunnett’s post hoc test, *p < 0.05 shows significant difference as compared to the IFN-γ/LPS-treated group (inflammation induced group). 200 μM L-NAME.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4487837&req=5

Fig3: Effect of MEMM on the nitric oxide (NO) production and RAW 264.7 cells’ viability. The assays were done in triplicate. One way ANOVA was followed by Dunnett’s post hoc test, *p < 0.05 shows significant difference as compared to the IFN-γ/LPS-treated group (inflammation induced group). 200 μM L-NAME.
Mentions: The in vitro effect of MEMM (12.5-100 μg/ml) on percentage of RAW 264.7 cell viability and NO production determined using the MTT assay is shown in Figure 3. The results showed that the MEMM, at all concentrations, did not affect cell viability. The extract was found to significantly (p < 0.05) increased the percentage of inhibition of NO production in LPS-induced RAW 264.7 cells. The amount of nitrite, a stable metabolite of NO, was used as the indicator of NO production in the medium. L-NAME, a standard NOS inhibitor, caused a significant inhibition of NO (p < 0.05). Quercitrin, on the other hand, also did not affect cell viability but caused significant (p < 0.05) inhibition of NO production.Figure 3

Bottom Line: The involvement of endogenous nitric oxide (NO) and sulfhydryl (SH) compounds in the gastroprotective effect of MEMM were also measured.MEMM inhibited the lipoxygenase (LOX) and xanthine oxidase (XO) activities with the highest affinity for the former while quercitrin showed high affinity for XO activity.MEMM exhibited a gastroprotective activity due partly to the presence of quercitrin, its antioxidant and anti-inflammatory activities, and via the modulation of NO and SH groups.

View Article: PubMed Central - PubMed

Affiliation: Halal Product Research Institute, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia. dr_zaz@yahoo.com.

ABSTRACT

Background: Melastoma malabathricum L. (Melastomaceae) is a small shrub with various medicinal uses. The present study was carried out to determine the gastroprotective mechanisms of methanol extract of M. malabathricum leaves (MEMM) in rats.

Methods: The extract's mechanisms of gastroprotection (50, 250, 500 mg/kg) were studied using the pylorus-ligation in rat model wherein volume, pH, free and total acidity of gastric juice, and gastric wall mucus content were determined. The involvement of endogenous nitric oxide (NO) and sulfhydryl (SH) compounds in the gastroprotective effect of MEMM were also measured. MEMM was subjected to the antioxidant, anti-inflammatory and phytochemical analysis and HPLC profiling.

Results: MEMM contained various phyto-constituents with quercitrin being identified as part of them. MEMM and quercitrin: i) significantly (p < 0.05) reduced the volume and acidity of gastric juice while increasing the pH and gastric wall mucus content.; ii) significantly (p < 0.05) increased the level of SOD, GTP and GTR while significantly (p < 0.05) reduced the level of CAT, MPO and TBARS activities.; iii) exerted gastroprotective activity when assessed using the ethanol-induced gastric ulcer assay, which was reversed by N(G)-nitro-L-arginine methyl esters (L-NAME; an inhibitor of NO synthase) and N-ethylmaleimide (NEM; a sulfhydryl (SH) blocker). MEMM inhibited the lipoxygenase (LOX) and xanthine oxidase (XO) activities with the highest affinity for the former while quercitrin showed high affinity for XO activity.

Conclusions: MEMM exhibited a gastroprotective activity due partly to the presence of quercitrin, its antioxidant and anti-inflammatory activities, and via the modulation of NO and SH groups.

No MeSH data available.


Related in: MedlinePlus