α-Terpineol Mitigates Dextran Sulfate Sodium-Induced Colitis in Rats by Attenuating Inflammation and Apoptosis

Integrative multi-omics reveals the mechanism of ulcerative colitis treated with Ma-Mu-Ran antidiarrheal capsules

RATIONALE

Ulcerative colitis (UC) is a chronic inflammatory gastrointestinal disease typically coexisting with intestinal microbiota dysbiosis, oxidative stress, and an inflammatory response. Although its underlying mechanism of action is unclear, Ma-Mu-Ran Antidiarrheal Capsules (MMRAC) have demonstrated significant therapeutic efficacy for UC.

METHODS

The mechanism of action of MMRAC in the treatment of UC model was investigated by combining metabolomics, transcriptomics, and intestinal microbiota detection techniques.

RESULTS

The high-dose group of MMRAC was determined as the best therapeutic dose by pathological changes and biochemical indexes. Transcriptome analysis revealed that 360 genes were differentially altered after MMRAC treatment. Metabolomic analysis using colon tissue yielded 14 colon tissue metabolites with significant differences. Intestinal flora analysis showed that 26 major microorganisms were identified at the genus level.

CONCLUSIONS

Based on a thorough multi-omics analysis of transcriptomics, metabolomics, and gut flora, it was determined that MMRAC regulated cysteine and methionine metabolism, arginine biosynthesis, and sphingolipid metabolism and their respective genes BHMT, PHGDH, iNOS, and SPHK1, which in turn served to inhibit UC-generated inflammatory responses and oxidative stress. Additionally, MMRAC regulated the abundance of Coprococcus, Helicobacter, Sutterella, Paraprevotella, and Roseburia in the intestinal tracts of UC mice, which was regulated toward normal levels, thereby restoring normal intestinal function.

The therapeutic effect of different cumin essential oil fractions against gastric ulcer in rats

Cumin, a popular spice, is widely used to treat stomach ailments in Central Asia and Xinjiang, China. Cumin essential oil has been found to effectively treat gastric ulcers, but its pharmacodynamic basis remains unclear. In this study, cumin essential oil was directly separated using column chromatography, and its components were identified through multi-dimensional gas chromatography-mass spectrometry. Finally, the cumin essential oil was fractionated into E1, E2, and E3. The effects of these fractions on gastric ulcers were studied using an anhydrous ethanol-induced rat model. The results indicated that the three fractions decreased ulcer index, gastric fluid pH, and pepsin activity to different extents. They lowered the levels of prostaglandin E2, gastrin, and epidermal growth factor in rat serum. According to an analysis of the above indices, E3 fraction had the best anti-ulcer effect. The detection results of the oxidative stress and inflammatory factors showed that all three fractions relieved the ethanol-induced oxidative stress and reduced the release of inflammatory factors to varying degrees. The E3 fraction played the most significant role. The E3 fraction was selected to explore the relevant mechanism, and the results showed that E3 fraction significantly prevented the cleaved caspase-3 and Bax protein levels that were ethanol-induced and resisted apoptosis induced by ethanol injury. The western blot results for detecting the NF-κB-related pathway protein showed that E3 fraction significantly inhibited the activation of p-p65, p-IKKβ, and p-IκBα. The study found that the E3 fraction of cumin essential oil had the most effective anti-ulcer effect by inhibiting NF-κB activation and apoptosis, thus reducing inflammation.

Zinc pyrithione ameliorates colitis in mice by interacting on intestinal epithelial TRPA1 and TRPV4 channels

AIMS

Although zinc pyrithione (ZPT) has been studied as topical antimicrobial and cosmetic consumer products, little is known about its pharmacological actions in gastrointestinal (GI) health and inflammation. Our aims were to investigate the effects of ZPT on transient receptor potential (TRP) channels and Ca2+ signaling in intestinal epithelial cells (IECs) and its therapeutic potential for colitis.

MAIN METHODS

Digital Ca2+ imaging and patch-clamp electrophysiology were performed on human colonic epithelial cells (HCoEpiC) and rat small intestinal epithelial cells (IEC-6). The transcription levels of proinflammatory cytokines such as IL-1β were detected by RTq-PCR. Dextran sulfate sodium (DSS) was used to induce colitis in mice.

KEY FINDINGS

ZPT dose-dependently induced Ca2+ signaling and membrane currents in IECs, which were attenuated by selective blockers of transient receptor potential ankyrin 1 (TRPA1) and transient receptor potential vanilloid 4 (TRPV4) channels, respectively. Interestingly, Ca2+ entry via TRPA1 channels inhibited the activity of TRPV4 channels in HCoEpiC, but not vice versa. ZPT significantly promoted migration of IECs by activating TRPA1 and TRPV4 channels. ZPT reversed lipopolysaccharides (LPS)-induced changes in mRNA expression of TRPA1 and TRPV4. Moreover, ZPT decreased mRNA levels of pro-inflammatory factors promoted by LPS in HCoEpiC, which were restored by selective TRPA1 blocker. In whole animal studies in vivo, ZPT significantly ameliorated DSS-induced body weight loss, colon shortening and increases in stool score, serum calprotectin and lactic acid (LD) in mouse model of colitis.

SIGNIFICANCE

ZPT exerts anti-colitic action likely by anti-inflammation and pro-mucosal healing through TRP channels in IECs. The present study not only expands pharmacology spectrum of ZPT in GI tract, but also repurposes it to a potential drug for colitis therapy.

Production of derivatives of α-terpineol by bacterial CYP102A1 enzymes

The monooxygenase activity of engineered CYP102A1 on α-terpineol was investigated. CYP102A1 M850 mutant (F11Y/R47L/D68G/F81I/F87V/E143G/L188Q/E267V/H408R) showed the highest catalytic activity toward α-terpineol among the engineered mutants produced by random mutagenesis. The major product (P1) of α-terpineol, p-menth-1-ene-3,8-diol, was characterized by high-performance liquid chromatography, gas-chromatography mass spectrometry, and nuclear magnetic resonance spectroscopy. Three minor products (P2-P4) of α-terpineol were considered as 6-hydroxy-α,α,4-trimethyl-3-cyclohexene-1-methanol (P2), trans-sobrerol (P3), and carvone hydrate (P4). Optimal conditions for product formation were determined as pH 7.0 and 30 °C. Production of p-menth-1-ene-3,8-diol was 0.87 mM at 1 h. Structure modeling using PyMOL and CAVER Web 1.2 server indicated that several mutations of CYP102A1 M850 were involved in access tunnels and active sites, resulting in increased activity toward α-terpineol. The major product, p-menth-1-ene-3,8-diol, of α-terpineol was produced by engineered CYP102A1 M850 via regioselective carbon hydroxylation. The engineered CYP102A1 could be a suitable biocatalyst for producing α-terpineol derivatives.

Thermosensitive and pH-responsive quercus infectoria gall-containing gel with long-lasting anti-inflammatory activity for ulcerative colitis

In the study, quercus infectoria gall (QIG) was used to develop a pH/thermosensitive gel in situ delivery system for enema administration of to treat acute ulcerative colitis (UC). The QIG ethanol extract pH/temperature-sensitive gel (QIG-pH-TSG) was characterized by using DSC, SEM, rheological and drug release analyses. The therapeutic effect in UC mice of the obtained gel were studied. The gel was maintained in a flowing liquid state under nonphysiological conditions (25 °C) to facilitate drug administration, and was transformed into a pseudoplastic liquid state under physiological conditions (37 °C), which prolonged its retention time in the colon. The gel drug was completely released within 24 h, and the temperature and viscosity of the gel were within the required range. In the in vitro anti-inflammatory test, QIG-pH-TSG decreased the level of TNF-α and IL-6, and increased IL-10 in RAW 264.7 actived by LPS. Moreover, the administration of QIG-pH-TSG resulted in a decrease in the colon histopathological score and an increase in colonic length, and also could reduce the IL-6, TNF-α, and C-reactive protein (CRP) levels in UC mice along with significant increases in IL-10 level in the colon. The QIG-pH-TSG could increase the concentration of QIG at the local inflammatory site and lead to an effective repair of the colonic mucosa. Therefore, the pH/thermosensitive in situ gel may serve as a drug delivery system for QIG to treat UC and overcome the limitations of some existing formulations. These results indicated that this composite gel was effectively in UC mice and the study provided a practical reference for the application of QIG-pH-TSG in the treatment of UC.

Role of diosmin in preventing doxorubicin-induced cardiac oxidative stress, inflammation, and hypertrophy: A mechanistic approach

Chemotherapeutic drugs, such as doxorubicin (Dox), are commonly used to treat a variety of malignancies. However, Dox-induced cardiotoxicity limits the drug's clinical applications. Hence, this study intended to investigate whether diosmin could prevent or limit Dox-induced cardiotoxicity in an animal setting. Thirty-two rats were separated into four distinct groups of controls, those treated with Dox (20 mg/kg, intraperitoneal, i.p.), those treated with diosmin 100 mg plus Dox, and those treated with diosmin 200 mg plus Dox. At the end of the experiment, rats were anesthetized and sacrificed and their blood and hearts were collected. Cardiac toxicity markers were analyzed in the blood, and the heart tissue was analyzed by the biochemical assays MDA, GSH, and CAT, western blot analysis (NF-kB, IL-6, TLR-4, TNF-α, iNOS, and COX-2), and gene expression analysis (β-MHC, BNP). Formalin-fixed tissue was used for histopathological studies. We demonstrated that a Dox insult resulted in increased oxidative stress, inflammation, and hypertrophy as shown by increased MDA levels and reduced GSH content and CAT activity. Furthermore, Dox treatment induced cardiac hypertrophy and damage, as evidenced by the biochemical analysis, ELISA, western blot analysis, and gene expression analysis. However, co-administration of diosmin at both doses, 100 mg and 200 mg, mitigated these alterations. Data derived from the current research revealed that the cardioprotective effect of diosmin was likely due to its ability to mitigate oxidative stress and inflammation. However, further study is required to investigate the protective effects of diosmin against Dox-induced cardiotoxicity.

Natural compounds target programmed cell death (PCD) signaling mechanism to treat ulcerative colitis: a review

Ulcerative colitis (UC) is a nonspecific inflammatory bowel disease characterized by abdominal pain, bloody diarrhea, weight loss, and colon shortening. However, UC is difficult to cure due to its high drug resistance rate and easy recurrence. Moreover, long-term inflammation and increased disease severity can lead to the development of colon cancer in some patients. Programmed cell death (PCD) is a gene-regulated cell death process that includes apoptosis, autophagy, necroptosis, ferroptosis, and pyroptosis. PCD plays a crucial role in maintaining body homeostasis and the development of organs and tissues. Abnormal PCD signaling is observed in the pathological process of UC, such as activating the apoptosis signaling pathway to promote the progression of UC. Targeting PCD may be a therapeutic strategy, and natural compounds have shown great potential in modulating key targets of PCD to treat UC. For instance, baicalin can regulate cell apoptosis to alleviate inflammatory infiltration and pathological damage. This review focuses on the specific expression of PCD and its interaction with multiple signaling pathways, such as NF-κB, Nrf2, MAPK, JAK/STAT, PI3K/AKT, NLRP3, GPX4, Bcl-2, etc., to elucidate the role of natural compounds in targeting PCD for the treatment of UC. This review used (ulcerative colitis) (programmed cell death) and (natural products) as keywords to search the related studies in PubMed and the Web of Science, and CNKI database of the past 10 years. This work retrieved 72 studies (65 from the past 5 years and 7 from the past 10 years), which aims to provide new treatment strategies for UC patients and serves as a foundation for the development of new drugs.

Plant Monoterpenes and Essential Oils as Potential Anti-Ageing Agents: Insights from Preclinical Data

Ageing is a natural process characterized by a time-dependent decline of physiological integrity that compromises functionality and inevitably leads to death. This decline is also quite relevant in major human pathologies, being a primary risk factor in neurodegenerative diseases, metabolic disorders, cardiovascular diseases and musculoskeletal disorders. Bearing this in mind, it is not surprising that research aiming at improving human health during this process has burst in the last decades. Importantly, major hallmarks of the ageing process and phenotype have been identified, this knowledge being quite relevant for future studies towards the identification of putative pharmaceutical targets, enabling the development of preventive/therapeutic strategies to improve health and longevity. In this context, aromatic plants have emerged as a source of potential bioactive volatile molecules, mainly monoterpenes, with many studies referring to their anti-ageing potential. Nevertheless, an integrated review on the current knowledge is lacking, with several research approaches studying isolated ageing hallmarks or referring to an overall anti-ageing effect, without depicting possible mechanisms of action. Herein, we aim to provide an updated systematization of the bioactive potential of volatile monoterpenes on recently proposed ageing hallmarks, and highlight the main mechanisms of action already identified, as well as possible chemical entity-activity relations. By gathering and categorizing the available scattered information, we also aim to identify important research gaps that could help pave the way for future research in the field.

Integrated characterization of filler tobacco leaves: HS-SPME-GC-MS, E-nose, and microbiome analysis across different origins

This study delves into the aroma characteristics and microbial composition of filler tobacco leaves (FTLs) sourced from six distinct cigar-growing regions within Yunnan, China, following standardized fermentation. An integrated approach using gas chromatography-mass spectrometry (GC-MS), electronic nose (E-nose), and microbiome analysis was employed for comprehensive profiling. Results derived from Linear Discriminant Analysis (LDA) using E-nose data confirmed the presence of notable variability in flavor substance profiles among the FTLs from six regions. Additionally, GC-MS was used to discern disparities in volatile organic compound (VOC) distribution across FTLs from these regions, identifying 92, 81, 79, 58, 69, and 92 VOCs within each respective sample set. Significantly, 24 VOCs emerged as pivotal determinants contributing to the heterogeneity of flavor profiles among FTLs from diverse origins, as indicated by Variable Importance for the Projection (VIP) analysis. Furthermore, distinctions in free amino acid content and chemical constituents were observed across FTLs. Of noteworthy significance, solanone, isophorone, durene, (-)-alpha-terpineol, and 2,3'-bipyridine exhibited the strongest correlations with microbiome data, with fungal microorganisms exerting a more pronounced influence on metabolites, as elucidated through two-way orthogonal partial least-squares (O2PLS) modeling. These findings provide a theoretical and technical basis for accurately evaluating the synchronization of FTLs in aromas and fermentation processes, and they will enhance the quality of fermented FTLs and foster the growth of the domestic cigar tobacco industry ultimately.