Biotechnological aspects of plants metabolites in the treatment of ulcer: A new prospective

Albizzia chinensis (Osbeck) Merr extract YS ameliorates ethanol-induced acute gastric ulcer injury in rats by regulating NRF2 signaling pathway

BACKGROUND

Around the world, there is a high incidence of gastric ulcers. YS, an extract from the Chinese herb Albizzia chinensis (Osbeck) Merr, has potential therapeutic applications for gastrointestinal diseases. Here we elucidated the protective effect and underlying mechanism of action of YS on gastric ulcer in rats injured by ethanol.

METHODS

The ethanol-induced gastric ulcer rat model was used to assess the protective effect of YS. A pathological examination of gastric tissue was performed by H&E staining. GES-1 cells damaged by hydrogen peroxide were used to simulate oxidative damage in gastric mucosal epithelial cells. Endogenous NRF2 was knocked down using small interfering RNA. Immunoprecipitation was used to detect ubiquitination of NRF2. Co-immunoprecipitation was used to detect the NRF2-Keap1 interaction.

RESULTS

YS (10 and 30 mg/kg, i.g.) significantly reduced the ulcer index, decreased MDA level, and increased SOD and GSH levels in gastric tissues damaged by ethanol. YS promoted NRF2 translocation from cytoplasm to nucleus and enhanced the NQO1 and HO-1 expression levels in injured rat gastric tissue. In addition, YS regulated NQO1 and HO-1 via NRF2 in H2O2-induced oxidative injured GES-1 cells. Further studies on the underlying mechanism indicated that YS reduced the interaction between NRF2 and Keap1 and decreased ubiquitylation of NRF2, thereby increasing its stability and expression of downstream factors. NRF2 knockdown abolished the effect of YS on MDA and SOD in GES-1 cells treated with H2O2.

CONCLUSION

YS reduced the NRF2-Keap1 interaction, promoting NRF2 translocation into the nucleus, which increasing the transcription and translation of NQO1 and HO-1 and improved the antioxidant capacity of rat stomach.

Gastroprotective Activities of Aqueous and 80% Methanol Leaf Extracts of Stephania abyssinica (Quart.-Dill. and A. Rich.) Walp. (Menispermaceae) in Rats

Background

An ethnobotanical study showed that the leaf of Stephania abyssinica (S. abyssinica) is used for the treatment of gastritis, but there is no scientific investigation.

Objective

The aim of this study was to evaluate the gastroprotective activities of both aqueous and 80% methanol leaf extracts of S. abyssinica in experimental rats.

Methods

Decoction and maceration techniques were used to prepare aqueous and 80% methanol leaf extracts, respectively. The extracts were evaluated against pyloric ligation, indomethacin, and ethanol-induced gastric ulcer models at doses of 100, 200, and 400 mg/kg. Negative control received 2% tween 80, while positive controls received 20 mg/kg of omeprazole and 100 µg/kg of misoprostol. Parameters, such as ulcer index, gastric mucin content, gastric juice volume, pH, and free and total acidity were measured.

Results

In the pyloric ligation induced gastric ulcer model, all doses of both extracts significantly reduced the ulcer index and gastric juice volume, while doses of 200 and 400 mg/kg exhibited a significant increment in mucus content and gastric juice pH as well as decrease in free and total acidity as compared to negative control. In indomethacin and ethanol induced gastric ulcer models, pretreatment with both extracts significantly reduced the ulcer index and enhanced gastric mucin content in a dose-dependent manner. Phytochemical screening of both extracts showed the existence of flavonoids, phenols, tannins, saponins, alkaloids, and coumarins with high contents of phenols, flavonoids, and alkaloids in 80% methanol extract.

Conclusion

This study revealed that aqueous and 80% methanol leaf extracts of S. abyssinica possessed remarkable gastroprotective activities against experimentally induced gastric ulcer models, and this possibly justify the traditional use of S. abyssinica leaves to treat gastritis.

Antioxidant and Gastroprotective Activity of Suaeda fruticosa Forssk. Ex J.F.Gmel

Suaeda fruticosa Forssk. Ex J.F.Gmel is traditionally used for inflammatory and digestive disorders, as a carminative, and for diarrhea. This plant is widely distributed in Asia, Africa, and the Mediterranean region. Aqueous methanolic extract of S. fruticosa (Sf.Cr) was prepared and screened for phytoconstituents through qualitative and GC-MS analysis. Quantification of total phenolic and flavonoid contents was performed, while antioxidant capacity was determined by DPPH, CUPRAC, FRAP, and ABTS assays. The gastroprotective activity was assessed in an ethanol-induced ulcer model. Gastric secretory parameters and macroscopic ulcerated lesions were analyzed and scored for ulcer severity. After scoring, histopathology was performed, and gastric mucus contents were determined. Oral pre-treatment of Sf.Cr demonstrated significant gastroprotection. The gastric ulcer severity score and ulcer index were reduced while the %-inhibition of ulcer was increased dose-dependently. The Sf.Cr significantly elevated the pH of gastric juice, while a decrease in total acidity and gastric juice volume was observed. Histopathology demonstrated less oedema and neutrophil infiltration in gastric mucosa of rats pre-treated with the Sf.Cr in comparison to ethanol-intoxicated animals. Furthermore, the gastric mucus contents were increased as determined by alcian blue binding. Sf.Cr showed marked gastroprotective activity, which can be attributed to antioxidant, antisecretory, and cytoprotective effects.

Algal Metabolites Can Be an Immune Booster against COVID-19 Pandemic

The world has faced the challenges of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for the last two years, first diagnosed at the end of 2019 in Wuhan and widely distributed worldwide. As a result, the WHO has proclaimed the illness brought on by this virus to be a global pandemic. To combat COVID-19, researcher communities continuously develop and implement rapid diagnoses, safe and effective vaccinations and other alternative therapeutic procedures. However, synthetic drug-related side effects and high costs have piqued scientists’ interest in natural product-based therapies and medicines. In this regard, antiviral substances derived from natural resources and some medicines have seen a boom in popularity. For instance, algae are a rich source of compounds such as lectins and sulfated polysaccharides, which have potent antiviral and immunity-boosting properties. Moreover, Algae-derived compounds or metabolites can be used as antibodies and vaccine raw materials against COVID-19. Furthermore, some algal species can boost immunity, reduce viral activity in humans and be recommended for usage as a COVID-19 preventative measure. However, this field of study is still in its early stages of development. Therefore, this review addresses critical characteristics of algal metabolites, their antioxidant potential and therapeutic potential in COVID-19.

Pharmacokinetics and Tissue Distribution Study of Modified Xiaochaihu Granules Against Gastric Ulcer Induced by Ethanol in Rats by UPLC-MS/MS

Gastric ulcer (GU) is one of the major gastrointestinal disorder diseases, with increasing incidence and prevalence globally. Modified Xiaochaihu granules (MXCHG) have been used effectively for treating chronic gastritis and GU clinically. To investigate the pharmacokinetics and tissue distribution of MXCHG, an ultraperformance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was established for the simultaneous determination of 8 bioactive ingredients (baicalin, wogonoside, baicalein, liquiritin, glycyrrhizic acid, berberine hydrochloride, saikosaponin a, and saikosaponin d) in rat plasma and various tissues using puerarin as an internal standard (IS). The biological samples were pretreated by protein precipitation with acetonitrile. The chromatographic separation was carried out on a C18 column with a gradient mobile phase consisting of acetonitrile and 0.1% formic acid in water. All analytes and IS were quantitated through ESI in the positive/negative ion multiple reaction monitoring mode. The mass transitions were as follows: m/z 445.0 → 268.5 for baicalin, m/z 458.7 → 282.8 for wogonoside, m/z 269.2 → 222.6 for baicalein, m/z 417.0 → 254.8 for liquiritin, m/z 822.1 → 350.8 for glycyrrhizic acid, m/ z 336.0 → 319.9 for berberine hydrochloride, m/z 780.3 → 618.5 for saikosaponin, and m/z 415.0 → 294.6 for the IS. The validated method was successfully applied to the pharmacokinetics and tissue distribution study of 8 compounds in rat plasma and tissues after the intragastric administration of MXCHG. The results demonstrated that 8 components were distributed widely and rapidly in various rat tissues after intravenous administration. Tissue deposition of the compounds in the rats was mainly in the small intestine and stomach. The present study can provide more useful information to guide the clinical use of MXCHG and the developed analytical method can also be applied for further clinical pharmacokinetic studies.