Nicotinamide alleviates indomethacin-induced gastric ulcers: a novel antiulcer agent

Licorice flavonoid ameliorates ethanol-induced gastric ulcer in rats by suppressing apoptosis via PI3K/AKT signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice is the dry roots and rhizomes of Glycyrrhiza uralensis Fisch., Glycyrrhiza glabra L. and Glycyrrhiza inflata Bat., which was first recorded in Shengnong's herbal classic. Licorice flavonoid (LF) is the main compound isolated from licorice with an indispensable action in treating gastric ulcer (GU). However, the underlying mechanisms need to be further explored.

AIM OF THE STUDY

This study aimed to investigate and further elucidate the mechanisms of LF against ethanol-induced GU using an integrated approach.

MATERIALS AND METHODS

The anti-GU effects of LF were evaluated in an ethanol-induced gastric injury rat model. Then, the metabolomics approach was applied to explore the specific metabolites and metabolic pathways. Next, the network pharmacology combined with metabolomics strategy was employed to predict the targets and pathways of LF for GU. Finally, these predictions were validated by molecular docking, RT-qPCR, and western blotting.

RESULTS

LF had a positive impact on gastric injury and regulated the expression of GU-related factors. Upon serum metabolomics analysis, 25 metabolic biomarkers of LF in GU treatment were identified, which were primarily involved in amino acid metabolism, carbohydrate metabolism, and other related processes. Subsequently, a "components-targets-metabolites" network was constructed, revealing six key targets (HSP90AA1, AKT1, MAPK1, EGFR, ESR1, PIK3CA) that may be associated with GU treatment. More importantly, KEGG analysis highlighted the importance of the PI3K/AKT pathway including key targets, as a critical route through which LF exerted its anti-GU effects. Molecular docking analyses confirmed that the core components of LF exhibited a strong affinity for key targets. Furthermore, RT-qPCR and western blotting results indicated that LF could reverse the expression of these targets, activate the PI3K/AKT pathway, and ultimately reduce apoptosis.

CONCLUSION

LF exerted a gastroprotective effect against gastric ulcer induced by ethanol, and the therapeutic mechanism may involve improving metabolism and suppressing apoptosis through the PI3K-AKT pathway.

Method Development for Simultaneously Determining Indomethacin and Nicotinamide in New Combination in Oral Dosage Formulations and Co-Amorphous Systems Using Three UV Spectrophotometric Techniques

This research aims to develop methods for simultaneously determining indomethacin (IND) and nicotinamide (NCT) in binary mixtures, immediate-release capsules, sustained-release capsules, and co-amorphous systems, which were designed in 2021 to improve the solubility, dissolution rate, and stability of the amorphous state of indomethacin. Moreover, this new combination may have also other possible medical benefits. Therefore, there is a need to have simple, sensitive, and precise developed methods for simultaneous quantification analysis of IND/NCT in several different ratios. Three UV-spectrophotometry techniques were deployed: zero-crossing point in the second-order derivative, dual-wavelength in the first-order derivative, and ratio subtraction coupled with spectrum subtraction. The limit of detection and the limit of quantifications (LOD and LOQ) for IND were 0.41 and 1.25, 0.55 and 1.66, and 0.53 and 1.62 μg/mL, respectively, while for NCT were 0.53 and 1.59, 0.38 and 1.14, and 0.36 and 1.08 μg/mL, respectively. All methods were linear at least in the range of 2.5-40.0 μg/mL. All proposed methods were validated according to ICH guidelines and their application on the dosage formulations was carried out. Finally, the proposed methods were compared to a reference method for each IND and NCT, and no significant statistical variance was found.

A prediction system: Regulating effect of small-molecule additives on properties of amorphous solid dispersions prepared by hot-melt extrusion technology

Amorphous solid dispersions (ASDs) with solubility advantage are suffering from the recrystallization risk and subsequent reduced dissolution triggered by high hygroscopicity of hydrophilic polymers and the supersaturation of ASD solutions. To address these issues, in this study, small-molecule additives (SMAs) in the Generally Recognized as Safe (GRAS) list were introduced into drug-polymer ASD. For the first time, we systematically revealed the intrinsic correlation between SMAs and properties of ASDs at the molecular level and constructed a prediction system for the regulation of properties of ASDs. The types and dosages of SMAs were screened by Hansen solubility and Flory-Huggins interaction parameters, as well as differential scanning calorimetry. X-ray photoelectron spectroscopy and adsorption energy (Eabs) calculation showed that the surface group distribution of ASDs and Eabs between ASD system and solvent were vital factors affecting the hygroscopicity and then stability. The radial distribution function revealed that interactions between components were proposed to be the critical factor for the dissolution performance. Based on this, a prediction system for regulating the properties of ASDs was successfully constructed mainly via molecular dynamics simulations and simple solid-state characterizations, and then validated by cases, which efficiently reduces the time and economic cost of pre-screening ASDs.

Novel Gastroprotective and Thermostable Cocrystal of Dimethyl Fumarate: Its Preparation, Characterization, and In Vitro and In Vivo Evaluation

Crystallization has revolutionized the field of solid-state formulations by modulating the physiochemical and release profile of active pharmaceutical ingredients (APIs). Dimethyl fumarate (DF), an FDA-approved first-line drug for relapsing-remitting multiple sclerosis, has a sublimation problem, leading to loss of the drug during its processing. To tackle this problem, DF cocrystal has been prepared by using solvent evaporation technique using nicotinamide as a coformer, which has been chosen based on in silico predictions and their ability to participate in hydrogen bonding. Fourier transform infrared (FT-IR), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and sublimation analysis have characterized the cocrystal and its thermostability. Comparative analysis of the release profile has been done by the dissolution and pharmacokinetic study of DF and its cocrystal. Formulated cocrystal is noncytotoxic, antioxidant and inhibits interleukin-6 and tissue necrosis factor-α in peripheral blood mononuclear cells induced by lipopolysaccharide. We have obtained a thermostable cocrystal of DF with a similar physicochemical and release profile to that of DF. The formulated cocrystal also provides a gastroprotective effect which helps counterbalance the adverse effects of DF by reducing lipid peroxidation and total nitrite levels.

Indomethacin co-amorphous drug-drug systems with improved solubility, supersaturation, dissolution rate and physical stability

In this study, new co-amorphous drug systems were designed using a pharmacologically relevant combination to improve the solubility and dissolution of indomethacin. Combinations of indomethacin-paracetamol (IND-PAR) as an anti-inflammatory/pain killer, and indomethacin-nicotinamide (IND-NCT) for prevention of gastric ulcers caused by IND, were developed for co-amorphization. The effect of PAR and NCT on the solubility, supersaturation, and dissolution of the poorly soluble counterpart, IND, was investigated. PAR and NCT were found to enhance the solubility and supersaturation of IND in biorelevant medium (FaSSIF) and in FaSSIF blank. Differential scanning calorimetry (DSC) showed capability of IND-PAR and IND-NCT binary mixtures to form eutectic mixture. Powder X-ray diffraction and DSC indicated the formation of a homogenous co-amorphous system with single T_g value. Hydrogen bonding between IND and each of PAR and NCT were found to stabilize the co-amorphous systems as supported by FTIR studies. The intrinsic dissolution rate under sink conditions was improved over that of plain amorphous IND both in FaSSIF and FaSSIF blank. IND-PAR 2:1 and IND-NCT 1:1 were extremely stable and remained amorphous for 7 months at 25 °C, while all co-amorphous formulations were stable at least up to one month at 40 °C under dry condition. The present work demonstrates an improved approach to combine IND-PAR and IND-NCT as promising co-amorphous systems for potential therapeutical applications.

The Contribution of Specific and Nonspecific Biomarkers in Diagnosis of Equine Gastric Ulcer Syndrome (EGUS) Under Field Condition

The aim of this study is to investigate the diagnostic efficiency of gastrin, pepsinogen, proinflammatory cytokines (TNF-α, IL-6), and oxidative stress biomarkers in horses with equine gastric ulcer syndrome (EGUS). Thirty horses diagnosed with gastroscopic EGUS and 15 clinically healthy horses were selected for this study. The serum levels of gastrin, pepsinogen showed nonsignificant changes in horses with EGUS when compared with healthy horses. The serum levels of TNF-α, IL-6 revealed a significant increase in horses with EGUS when compared with healthy ones. Oxidative stress is evident in horses with EGUS in comparison with healthy horses as detected by higher levels of malondialdehyde (MDA) and decreased serum levels of total antioxidant capacity (TAC), Superoxide dismutase (SOD), glutathione (GSH), and nitric oxide (NO). MDA and TNF-α showed better sensitivity and specificity than IL-6 in distinguishing horses with EGUS from control horses. Conclusively, examination of serum gastrin and pepsinogen levels had a limited value in diagnosis of EGUS in horses under investigation. Moreover, this study showed that oxidative stress is evident in horses with EGUS. Higher levels of TNF-α and IL-6 indicate their role in EGUS pathogenesis in horses. Finally, MDA, TNF-α, and IL-6 could be used as biological markers for preliminary screening of horses with EGUS. Gastroscopy still accredited as the "gold standard" for diagnosis EGUS.

Antiulcer Effect of Honey in Nonsteroidal Anti-Inflammatory Drugs Induced Gastric Ulcer Model in Rats: A Systematic Review

Background

Peptic ulcer is a basic term for ulcers on the lower oesophagus, stomach, or jejunum. The specific term for ulcer in the stomach is gastric ulcer. The extensive use of honey around the globe helps researchers to study the usefulness of honey. Many studies had already been conducted and proved the effectiveness of honey in treating gastric ulcer.

Methods

A systematic review of the literature was conducted to identify relevant studies on honey used as an alternative treatment of gastric ulcer cause by NSAIDs. A comprehensive search was conducted in Medline, SCOPUS, and Ebscohost. The main criteria used were articles published in English and using NSAIDs-induced gastric ulcer in rat's model and those reporting the effectiveness of honey.

Results

Articles published between 2001 and 2014 were identified to be relevant in studies related to the inclusion criteria. The literature search found 30 potential and closely related articles in this review, but only 5 articles were taken which meet the criteria needed to be fulfilled.

Conclusions

All studies in this review reported the efficacy of honey for gastric ulcer based on its antioxidant and cytoprotective activities. Most of the studies conducted used different types of honey at various doses on rats. Future studies should be conducted to identify the appropriate dose for humans to achieve similar gastroprotective effects.

Complementarity of in vitro and in vivo models for the evaluation of gastro-protective effects of pharmacological substances

Gastric mucosa is frequently exposed to various gastric irritants, and there is a continuing requirement to develop new gastro-protective agents. This study compares the effects of three such agents, sucralfate, rebamipide, and cimetidine in both in vivo and in vitro indomethacin-induced gastric damage models. For the in vivo approach, rats were orally administered sucralfate, rebamipide, and cimetidine at 300 mg/kg before an acute dose of indomethacin (30 mg/kg). Gastric lesions were then macroscopically examined. For the in vitro approach, gastric mucosal cells were incubated with sucralfate (3 and 5 mg/mL), rebamipide (0.3 and 1 mm), and cimetidine (10 and 50 μg/mL) before exposure to indomethacin (3.8 mm). The release of lactate dehydrogenase (LDH) and mitochondrial function were then measured. Sucralfate, rebamipide, and cimetidine displayed gastro-protective effects in vivo (decreased number of gastric ulcers: -50% P < 0.05, -22% NS, and -69% P < 0.05, respectively, and reduced length of gastric lesions: -62% P < 0.05, -29% NS, and -70% P < 0.001, respectively). Cell damage induced by indomethacin in vitro was inhibited by sucralfate (LDH release) and by rebamipide and cimetidine (mitochondrial function and LDH release). In contrast, sucralfate accentuated the indomethacin-induced decrease in mitochondrial function. Although cultured gastric cells offer a promising tool for evaluating the cytotoxic or protective effects of test compounds, data from in vivo models are still needed to confirm in vitro data. Using both approaches provides more comprehensive insight into the effects of test compounds on the gastric mucosa.

Role of nicotinamide (vitamin B3) in acetaminophen-induced changes in rat liver: Nicotinamide effect in acetaminophen-damged liver

Acetaminophen is a widely used analgesic and antipyretic agent, which is safe at therapeutic doses. However, overdoses of acetaminophen induce severe oxidative stress, which leads to acute liver failure. Nicotinamide has proven effective in ameliorating many pathological conditions that occur due to oxidative stress. This study verifies the prophylactic and therapeutic effects of nicotinamide against the hepatic pathophysiological and ultrastructural alterations induced by acetaminophen. Wistar rats intoxicated with an acute overdose of acetaminophen (5g/kg b.wt) were given a single dose of nicotinamide (500mg/kg b.wt) either before or after intoxication. Acetaminophen caused significant elevation in the liver functions and lipid peroxidation marker, and decline in the activities of the hepatic antioxidant enzymes. This oxidative injury was associated with hepatic centrilobular necrosis, hemorrage, vacuolar degeneration, lipid accumulation and mitochondrial alterations. Treating intoxicated rats with nicotinamide (500mg/kg) significantly ameliorated acetaminophen-induced biochemical changes and pathological injuries. However, administering the same dose of nicotinamide to healthy animals or prior to acetaminophen-intoxication induced hepatotoxicity. Caution should be taken when administering high doses of NAM because of its possible hepatotoxicity. Considering the wide use of nicotinamide, there is an important need for monitoring nicotinamide tolerance, safety and efficacy in healthy and diseased subjects.

Diosmin protects against ethanol-induced gastric injury in rats: novel anti-ulcer actions

Alcohol consumption has been commonly associated with gastric mucosal lesions including gastric ulcer. Diosmin (DIO) is a natural citrus flavone with remarkable antioxidant and anti-inflammatory features that underlay its protection against cardiac, hepatic and renal injuries. However, its impact on gastric ulcer has not yet been elucidated. Thus, the current study aimed to investigate the potential protective effects of DIO against ethanol-induced gastric injury in rats. Pretreatment with DIO (100 mg/kg p.o.) attenuated the severity of ethanol gastric mucosal damage as evidenced by lowering of ulcer index (UI) scores, area of gastric lesions, histopathologic aberrations and leukocyte invasion. These actions were analogous to those exerted by the reference antiulcer sucralfate. DIO suppressed gastric inflammation by curbing of myeloperoxidase (MPO) and tumor necrosis factor-α (TNF-α) levels along with nuclear factor kappa B (NF-κB) p65 expression. It also augmented the anti-inflammatory interleukin-10 (IL-10) levels. Meanwhile, DIO halted gastric oxidative stress via inhibition of lipid peroxides with concomitant enhancement of glutathione (GSH), glutathione peroxidase (GPx) and the total antioxidant capacity (TAC). With respect to gastric mucosal apoptosis, DIO suppressed caspase-3 activity and cytochrome C (Cyt C) with enhancement of the anti-apoptotic B cell lymphoma-2 (Bcl-2) in favor of cell survival. These favorable actions were associated with upregulation of the gastric cytoprotective prostaglandin E₂ (PGE₂) and nitric oxide (NO). Together, these findings accentuate the gastroprotective actions of DIO in ethanol gastric injury which were mediated via concerted multi-pronged actions, including suppression of gastric inflammation, oxidative stress and apoptosis besides boosting of the antioxidant and the cytoprotective defenses.

The biochemical pathways of central nervous system neural degeneration in niacin deficiency

Neural degeneration is a very complicated process. In spite of all the advancements in the molecular chemistry, there are many unknown aspects of the phenomena of neurodegeneration which need to be put together. It is a common sequela of the conditions of niacin deficiency. Neural degeneration in Pellagra manifests as chromatolysis mainly in pyramidal followed by other neurons and glial cells. However, there is a gross lack of understanding of biochemical mechanisms of neurodegeneration in niacin deficiency states. Because of the necessity of niacin or its amide derivative NAD in a number of biochemical pathways, it is understandable that several of these pathways may be involved in the common outcome of neural degeneration. Here, we highlight five pathways that could be involved in the neuraldegeneration for which evidence has accumulated through several studies. These pathways are: 1) the tryptophan-kyneurenic acid pathway, 2) the mitochondrial ATP generation related pathways, 3) the poly (ADP-ibose) polymerase (PARP) pathway, 4) the BDNF-TRKB Axis abnormalities, 5) the genetic influences of niacin deficiency.

The anti-inflammatory and antioxidative effects of nicotinamide, a vitamin B(3) derivative, are elicited by FoxO3 in human gestational tissues: implications for preterm birth

The inflammatory process plays a pivotal role during the pathogenesis of human labour, both at term and at preterm. Nicotinamide, a vitamin B(3) derivative, exerts anti-inflammatory and antioxidative properties in several cell types by interaction with various intracellular signalling proteins via modulating the activity of various transcription factors, including activation of the O subfamily of Forkhead/winged helix transcription factors (FoxO) and inhibition of nuclear factor-κB (NF-κB). The aim of this study was to determine the effect of nicotinamide on the expression of pro-labour and mediators in human placenta. The effects of nicotinamide were evaluated, over 24 h, by treating placenta with 0, 25 and 50 mM nicotinamide in the absence or presence of 10 μg/ml lipopolysaccharide (LPS). Nicotinamide treatment resulted in a significant reduction of basal and/or LPS-stimulated release and gene expression of the pro-inflammatory cytokines TNF-α, IL-6 and the chemokine IL-8, and the release of the prostaglandins PGE(2) and PGF(2)α and cyclooxygenase (COX)-2 mRNA expression. Additionally, nicotinamide treatment of human placenta resulted in attenuation of basal and LPS-induced oxidative stress, reducing 8-isoprostane release and increasing gene expression of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT). There was no effect of nicotinamide on NF-κB activation. The anti-inflammatory and antioxidant actions of nicotinamide were abolished by knockdown of FoxO3 using siRNA. In conclusion, nicotinamide exerts anti-inflammatory and antioxidative effects in human placenta, in part, via activation of FoxO3. Further studies should be undertaken to define a possible implication of vitamin B(3) derivatives in the management of preterm labour and delivery.

Role of nicotinamide in DNA damage, mutagenesis, and DNA repair

Nicotinamide is a water-soluble amide form of niacin (nicotinic acid or vitamin B3). Both niacin and nicotinamide are widely available in plant and animal foods, and niacin can also be endogenously synthesized in the liver from dietary tryptophan. Nicotinamide is also commercially available in vitamin supplements and in a range of cosmetic, hair, and skin preparations. Nicotinamide is the primary precursor of nicotinamide adenine dinucleotide (NAD⁺), an essential coenzyme in ATP production and the sole substrate of the nuclear enzyme poly-ADP-ribose polymerase-1 (PARP-1). Numerous in vitro and in vivo studies have clearly shown that PARP-1 and NAD⁺ status influence cellular responses to genotoxicity which can lead to mutagenesis and cancer formation. This paper will examine the role of nicotinamide in the protection from carcinogenesis, DNA repair, and maintenance of genomic stability.