Ethanol-Induced Gastric Injury: Microscopic Analysis of the Protective Effect of Frutalin

Isolation, purification, and characterization of lectins from medicinal plant Combretum glutinosum seeds endowed with analgesic and antiulcer properties

In the pursuit of safer and more effective treatments, there is a growing interest in plant-derived compounds, particularly lectins, because of their diverse pharmacological properties. This study focused on isolating, purifying, and characterizing lectin from Combretum glutinosum seeds (CGSLs) to assess its potential as an analgesic and antiulcer agent. CGSL extraction involved defatting and buffer extraction, followed by purification using ammonium sulfate fractionation and fetuin-agarose affinity column chromatography. The isolectins (iso-CGSLs), each consisting of 60 kDa and 57 kDa heterodimeric subunits, displayed glycoprotein properties with a 40 % neutral sugar content. They exhibited peak activity at 55 °C and remained stable for up to the fifth day at room temperature. The activity exhibited a pH dependence, peaking between 7.5 and 10.5, and all seemingly operated independently of metal ions. CGSL, at optimal doses ranging from 6 to 12 mg/kg, had significant analgesic effects on acetic acid-induced writhing and hot plate tests in mice. Evaluation using 0.7 % acetic acid resulted in notable pain reduction across all doses (P < 0.05). The analgesic effect of lectin was partially reversed by naloxone (a morphine antagonist), indicating partial involvement of the opioid receptor system. Furthermore, CGSL exhibited antiulcer effects in ethanol-induced gastric ulcer models in rats, highlighting its therapeutic potential as a natural alternative for analgesic and antiulcer treatments.

Gastroprotective activity and physicochemical analysis of carboxymethylated gum from Anadenanthera colubrina

Biotechnological advancements require the physicochemical alteration of molecules to enhance their biological efficacy for the effective treatment of gastric ulcers. The study aimed to produce a polyelectrolytic compound from red angico gum (AG) by carboxymethylation, evaluate its physicochemical characteristics and investigate gastric protection against ethanol-induced ulcers. AG and carboxymethylated angico gum (CAG) were characterized by Fourier transform infrared spectroscopy, determination of the degree of substitution and gel permeation chromatography (GPC) and 13C NMR techniques. The results demonstrated that the modification of the polymer was satisfactory, presenting conformational changes e improving the interaction with the gastric mucosa. AG and CAG reduced macroscopic and microscopic damage such as edema, hemorrhage and cell loss caused by exposure of the mucosa to alcohol. Both demonstrated antioxidant activity in vitro, and in vivo, pretreatment with gums led to the restoration of superoxide dismutase and glutathione levels compared to the injured group. Concurrently, the levels of malondialdehyde and nitrite decreased. Atomic force microscopy showed that CAG presented better conformational properties of affinity and protection with the gastric mucosa compared to AG in the acidic pH. Based on our findings, it is suggested that this compound holds promise as a prospective product for future biotechnological applications.

Activation of transient receptor potential vanilloid channel 4 contributes to the development of ethanol-induced gastric injury in mice

The transient receptor potential vanilloid channel 4 (TRPV4) is associated with the development of several pathologies, particularly gastric disorders. However, there are no studies associating this receptor with the pathophysiology of gastric erosions. The aim of this study was to investigate the role of TRPV4 in the development of ethanol-induced gastric damage in vivo. Gastric lesions were induced by ethanol in Swiss mice pretreated with TRPV4 antagonists, GSK2193874 (0.1; 0.3 and 0.9 mg/kg) or Ruthenium red (0.03; 0.1 or 0.3 mg/kg) or its agonist, GSK1016790A (0.9 mg/kg). Gastric mucosal samples were taken for histopathology, immunohistochemistry, atomic force microscopy and evaluation of antioxidant parameters. The gastric mucus content and TRPV4 mRNA expression were analyzed. Ethanol exposure induced upregulation of gastric mRNA and protein expression of TRPV4. TRPV4 blockade promoted gastroprotection against ethanol-induced injury on macro- and microscopic levels, leading to reduced hemorrhage, cell loss and edema and enhanced gastric mucosal integrity. Moreover, an increase in superoxide dismutase (SOD) and glutathione (GSH) activity was observed, followed by a decrease in malondialdehyde (MDA) levels. TRPV4 blockade during alcohol challenge reestablished gastric mucus content. The combination of TRPV4 agonist and ethanol revealed macroscopic exacerbation of gastric damage area. Our results confirmed the association of TRPV4 with the development of gastric injury, showing the importance of this receptor for further investigations in the field of gastrointestinal pathophysiology and pharmacology.