Gastroprotective effect of diligustilide isolated from roots of Ligusticum porteri coulter & rose (Apiaceae) on ethanol-induced lesions in rats

Dissolving sodium hydrosulfide in drinking water is not a good source of hydrogen sulfide for animal studies

Hydrogen sulfide (H2S) has many physiological and pathological roles in the human body. Sodium hydrosulfide (NaHS) is widely used as a pharmacological tool for assessing H2S effects in biological experiments. Although H2S loss from NaHS solution is a matter of minutes, some animal studies use NaHS in solution as an H2S-donating compound in drinking water. This study addresses whether 30 μM NaHS in drinking water prepared in rat/mouse water bottles remains stable for at least 12-24 h, as presumed by some authors. NaHS solutions (30 μM) were prepared in drinking water and immediately transferred to rat/mice water bottles. Samples were obtained from the tip of water bottles and from inside of the bottles at 0, 1, 2, 3, 4, 5, 6, 12, and 24 h for sulfide measurement using the methylene blue method. Furthermore, NaHS (30 μM) was administered to male and female rats for two weeks, and serum sulfide concentrations were measured every other day in the first week and at the end of the second week. NaHS solution was unstable in the samples obtained from the tip of water bottles; it declined by 72% and 75% after 12 and 24 h, respectively. In the samples obtained from the inside of the water bottles, the decline in the NaHS was not significant until 2 h; however, it decreased by 47% and 72% after 12 and 24 h, respectively. NaHS administration did not affect serum sulfide levels in male and female rats. In conclusion, NaHS solution prepared in drinking water can not be used for H2S donation as the solution is unstable. This route of administration exposes animals to variable and lower-than-expected amounts of NaHS.

Sonchus oleraceus L. Promotes Gastroprotection in Rodents via Antioxidant, Anti-Inflammatory, and Antisecretory Activities

Sonchus oleraceus L. is an edible and medicinal plant used to treat stomachache and gastric ailments around the world. Thus, this study aimed to determine the gastroprotective mode of action of hydroalcoholic extract of S. oleraceus (HES). Mice were treated with HES before induction of gastric ulceration by ethanol/HCl. The area and histological appearance of ulcers were quantified, and mucus was measured histochemically. The effects of HES on inflammatory and oxidative markers were assessed in the ulcerated tissue. In addition, we investigated the gastric acid antisecretory activity of HES in pylorus-ligated rats. Chemical analyses of HES and its antioxidant activity were also performed in vitro. The HES (30 or 300 mg/kg) reduced the ulceration by 71.5 and 76.2%, respectively, compared with vehicle (p < 0.001), and the histological analysis confirmed the macroscopic results with elevation in mucin levels by 361.4 and 477.5%, respectively, compared with vehicle (p < 0.001). Moreover, the gastroprotection was accompanied by increases in GSH levels and in SOD, CAT, and GST activities; in parallel to a reduction in MPO activity and TNF levels. Furthermore, HES reduced the total acidity, and pepsin activity of the gastric juice of rats by 61 and 63%, respectively, compared to the vehicle. Phytochemical analysis indicated that luteolin-7-O-β-D-glucoside is the main active compound annotated in HES. Was also found that HES scavenged the DPPH radical with an IC₅₀ of 15.41 μg/mL. In conclusion, the gastroprotective effects of HES involve reductions in oxidative stress and inflammatory injury, in conjunction with an increase in mucus layer and inhibition of gastric secretion. This study advances in elucidating the modes of the antiulcer potential of S. oleraceus and contributes to the prospection of new gastroprotective molecules.

Effect of the proportion of curcuminoids on the gastroprotective action of Curcuma longa L. in rats

The gastroprotective effect of a turmeric acetone extract (TAE) (Curcuma longa L. [Zingiberaceae]) was evaluated and compared against its major curcuminoids; curcumin (CUR), demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC). Additionally, to demonstrate the importance of the metabolites' ratio in the extract on the synergistic effect, different mixtures were evaluated. An ethanol-induced gastric injury model was used to evaluate the gastroprotection activity in Wistar rats. The pharmacologic interaction analysis was performed using the Combination Index (CI)-Isobologram Equation method. The CI calculated at 0.5 of affected fraction (fa) for the TAE indicated a synergistic interaction between its components. However, when the proportion of curcuminoids changed from 3.7:1:10 in TAE to a 1:1:1 ratio, the CI implied an antagonistic effect. The binary combinations of curcuminoids (1:1) also showed an antagonistic interaction. The results of this work suggest that the proportion of curcuminoids in the TAE is crucial for the gastroprotective effect against ethanol-induced damage.

Mexican Plants and Derivates Compounds as Alternative for Inflammatory and Neuropathic Pain Treatment-A Review

Despite the availability of many anti-pain drugs, in the form of NSAIDs, steroids, gabapentinoids, opioids, and antidepressants, in this study we address the natural compounds belonging to the group of Mexican medicinal plants or "Mexican folk medicine", used for pain management in Mexico. Our interest in this subject is due to the growing idea that "natural is harmless" and to the large number of side effects exhibited in pharmacotherapy. The objective of this review was to document the scientific evidence about Mexican medicinal plants and their derivatives used for inflammatory and neuropathic pain treatment, as well as the mechanisms of action implicated in their antinociceptive effects, their possible adverse effects, and the main pharmacological aspects of each plant or compound. Our data review suggested that most studies on Mexican medicinal plants have used inflammatory experimental models for testing. The anti-pain properties exerted by medicinal plants lack adverse effects, and their toxicological assays report that they are safe to consume; therefore, more studies should be performed on preclinical neuropathic pain models. Moreover, there is no convincing evidence about the possible mechanisms of action involved in the anti-pain properties exerted by Mexican plants. Therefore, the isolation and pharmacological characterization of these plant derivatives' compounds will be important in the design of future preclinical studies.

Levistolide A Attenuates Alzheimer's Pathology Through Activation of the PPARγ Pathway

Alzheimer's disease (AD) is a neurodegenerative disease characterized by β-amyloid (Aβ) protein deposition, neurofibrillary tangle (NFT) formation, and neuronal loss in the brain. The current study was designed to investigate the potential mechanisms by which levistolide A affects the pathogenesis of AD in an amyloid precursor protein/presenilin 1 (APP/PS1) transgenic (Tg) mouse model of AD and N2a/APP695swe cells. Specifically, behavioral changes in levistolide A-treated APP/PS1 Tg mice were assessed by the nest-building and Morris water maze (MWM) tests. Levistolide A treatment clearly ameliorated memory deficits and cognitive decline in APP/PS1 Tg mice. Aβ generation and the inflammatory response in APP/PS1 Tg mouse brains were clearly reduced after long-term levistolide A application. Mechanistically, levistolide A concurrently stimulated the expression of α-secretase and decreased the generation of β- and γ-secretases. In addition, levistolide A inhibited the phosphorylation of tau in the brains of the Tg mice. Furthermore, in vitro and in vivo experiments suggested that peroxisome proliferator-activated receptor γ (PPARγ) is the key transcription factor that mediates the regulatory effects of levistolide A on the expression of α-, β-, and γ-secretases and phosphorylation of tau. Collectively, these findings show that levistolide A may be a candidate for the treatment of AD.

Medicinal Plants in the Treatment of Peptic Ulcer Disease: A Review

Peptic Ulcer Disease (PUD) is the most common disorder of the stomach and duodenum, which is associated with Helicobacter pylori infection. PUD occurs due to an imbalance between offensive and defensive factors and Proton Pump Inhibitors (PPI), Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) and antibiotics are frequently used for the treatment. Recently, medicinal plants have emerged as efficacious, safe and widely available alternative therapies for PUD. The aim of this review was to study the medicinal plants and phytochemicals, which have been used for PUD treatment to evaluate the potential role of natural compounds to develop herbal remedies for PUD. Information was obtained using a literature search of electronic databases, such as Web of Science, Google Scholar, PubMed, Sci Finder, Reaxys and Cochrane. Common and scientific names of the plants and keywords such as 'peptic ulcer', 'gastric ulcer', 'stomach ulcer' and 'duodenal ulcer' were used for search. Eventually, 279 plants from 89 families were identified and information on the plant families, part of the plant used, chemical constituents, extracts, ulcer model used and dosage were abstracted. The results indicated that most of the anti-PUD plants were from Asteraceae (7.1%) and Fabaceae (6.8%) families while flavonoids (49%), tannins (13%), saponins (10%) and alkaloids (9%) were the most common natural compounds in plants with anti-PUD activity.

Anti-inflammatory, antioxidant, and gaso-protective mechanism of 3α-hydroxymasticadienoic acid and diligustilide combination on indomethacin gastric damage

The co-administration of 3α-hydroxymasticadienoic acid (3α-OH MDA) and diligustilide (DLG) generates a synergist gastroprotective effect on indomethacin-induced gastric damage. However, the related protective activities of the compounds alone (or in combination) remain unclear. In the present study, we evaluated the anti-inflammatory and antioxidative activities, as well as the potential modulation of important gasotransmitters of each compound individually and in combination using the indomethacin-induced gastric damage model. Male Wistar rats were treated orally with the 3α-OH MDA, DLG, or their combination (at a fixed ratio of 1:1, 1:3, and 3:1) 30 min before the generation of gastric mucosal lesions with indomethacin (30 mg/kg, p.o.). Three hours later, the gastric injury (mm²) was determined. Results from these experiments indicate, in addition to maintaining basal levels of PGE₂, the gastroprotective effect of the pre-treatment with 3α-OH MDA (70%), DLG (81%), and their combination (72%) which was accompanied by significant decreases in leukocyte recruitment, as well as decreases in TNF-α and LTB₄ gastric levels (p < 0.05). We also found that the pre-treatment maintains the basal antioxidant enzyme activities (SOD) and gastric NO and H₂S production even in the presence of indomethacin (p < 0.05). In conclusion, when 3α-OH MDA-DLG is given at a 1:1 combination ratio, the gastroprotective effect and the inflammatory, antioxidant, and gaso-modulation properties are not different from those of treatments using the maximum doses of each compound, revealing that this combination produces promising results for the treatment of gastric ulcers.

Mucoadhesive effect of Curcuma longa extract and curcumin decreases the ranitidine effect, but not bismuth subsalicylate on ethanol-induced ulcer model

The study of pharmacological interactions between herbal remedies and conventional drugs is important because consuming traditional herbal remedies as supplements or alternative medicine is fairly common and their concomitant administration with prescribed drugs could either have a favorable or unfavorable effect. Therefore, this work aims to determine the pharmacological interactions of a turmeric acetone extract (TAE) and its main metabolite (curcumin) with common anti-ulcer drugs (ranitidine and bismuth subsalicylate), using an ethanol-induced ulcer model in Wistar rats. The analysis of the interactions was carried out via the Combination Index-Isobologram Equation method. The combination index (CI) calculated at 0.5 of the affected fraction (fa) indicated that the TAE or curcumin in combination with ranitidine had a subadditive interaction. The results suggest that this antagonistic mechanism is associated to the mucoadhesion of curcumin and the TAE, determined by rheological measurements. Contrastingly, both the TAE and curcumin combined with bismuth subsalicylate had an additive relationship, which means that there is no pharmacological interaction. This agrees with the normalized isobolograms obtained for each combination. The results of this study suggest that mucoadhesion of curcumin and the TAE could interfere in the effectiveness of ranitidine, and even other drugs.

Structural Reassignment of rel-(3'Z,3R,6R,7R,3a'R,6'R)-3,8-Dihydrodiligustilide and the Activity of Diligustilide and 3,8-Dihydro- and 3,8,7',7a'-Tetrahydrodiligustilides as Progestins

Several phthalides were semisynthesized, including a 3,8-dihydrodiligustilide with progesterone-like activity, previously isolated from Ligusticum chuanxiong, the structure of which was earlier assigned to a semisynthetic product with nonidentical spectroscopic constants. The structure of this natural phthalide was reassigned with a proposal of its absolute configuration. Phthalides acted as progestins in cell viability assays, immunofluorescence microscopy, and docking analysis. Therefore, the structures for natural and semisynthetic phthalides with potential use in hormone-related therapies were reassigned.

Chemistry and Biology of Selected Mexican Medicinal Plants

Herbal medicines are an integral element of alternative medical care in Mexico, and the best testimony to their efficacy and cultural value is their persistence in contemporary Mexican marketplaces where the highest percentages of medicinal and aromatic plants are sold. This chapter summarizes current trends in research on medicinal plants in Mexico, with emphasis on work carried out at the authors' laboratories. The most relevant phytochemical and pharmacological profiles of a selected group of plants used widely for treating major national health problems are described.From this contribution, it is evident that in the last five decades a significant amount of research on medicinal plants has been performed by Mexican scientists. Such efforts have led to the publication of many research papers in noted peer-reviewed journals and technical books. The isolation and structural characterization of hundreds of bioactive secondary metabolites have been accomplished, and most importantly, these studies have tended to support the ethnomedical uses of many different species. A multidisciplinary approach for investigating these plants has led to an increased emphasis on areas such as phytopharmacology, phytotoxicology, quality control, regulation, and conservation issues for these valuable resources. The medicinal plants analyzed so far have shown a very broad chemical diversity of their constituents, which have a high potential for exhibiting novel mechanistic effects biologically. The chapter shows also that there is need to conduct additional clinical studies on herbal drugs, in particular because the longstanding traditional evidence for their safety is not always sufficient to assure their rational use. There is also need to move to "omics" approaches for investigating the holistic effect and the influence of groups of phytochemicals on the whole organism. Mexican scientists may be expected to have bright prospects in this regard, which will imbue medicinal plant research with a new dynamism in the future.