ABSTRACT
Bitter taste receptors, also known as taste 2 receptors (T2R), are expressed throughout the body and are involved in regulating different physiological processes. T2R expression in the intestinal tract regulates orexigenic and anorexigenic peptide secretion, thus becoming potential a potential target for controlling food intake and the prevalence of obesity and overweight. The present study aims to investigate the implication of hop bitter compounds such as α-acids, ß-acids, and xanthohumol in the secretion of anorexigenic hormones and T2R expression in intestinal STC-1 cells. The tested bitter compounds induced the secretion of the anorexigenic hormones glucagon-like peptide 1 and cholecystokinin concurrently with a selective increase of murine Tas2r expression. Xanthohumol and α-acids selectively increase Tas2r138 and Tas2r130-Tas2r138 expression, respectively, in STC-1 cells, while ß-acids increased the expression of all bitter receptors studied, including Tas2r119, Tas2r105, Tas2r138, Tas2r120, and Tas2r130. Increased intracellular calcium levels confirmed this activity. As all investigated bitter molecules increased Tas2r138 expression, computational studies were performed on Tas2r138 and its human orthologue T2R38 for the first time. Molecular docking experiments showed that all molecules might be able to bind both bitter receptors, providing an excellent basis for applying hop bitter molecules as lead compounds to further design gastrointestinal-permeable T2R agonists.
ABSTRACT
Withania somnifera (L.) Dunal is a medicinal plant belonging to the traditional Indian medical system, showing various therapeutic effects such as anti-cancer, anti-inflammatory, anti-microbial, anti-diabetic, and hepatoprotective activity. Of great interest is W. somnifera's potential beneficial effect against neurodegenerative diseases, since the authorized medicinal treatments can only delay disease progression and provide symptomatic relief and are not without side effects. A systematic search of PubMed and Scopus databases was performed to identify preclinical and clinical studies focusing on the applications of W. somnifera in preventing neurodegenerative diseases. Only English articles and those containing the keywords (Withania somnifera AND "neurodegenerative diseases", "neuroprotective effects", "Huntington", "Parkinson", "Alzheimer", "Amyotrophic Lateral Sclerosis", "neurological disorders") in the title or abstract were considered. Reviews, editorials, letters, meta-analyses, conference papers, short surveys, and book chapters were not considered. Selected articles were grouped by pathologies and summarized, considering the mechanism of action. The quality assessment and the risk of bias were performed using the Cochrane Handbook for Systematic Reviews of Interventions checklist. This review uses a systematic approach to summarize the results from 60 investigations to highlight the potential role of W. somnifera and its specialized metabolites in treating or preventing neurodegenerative diseases.
ABSTRACT
Efferent sympathetic nerve fibers regulate several renal functions activating norepinephrine receptors on tubular epithelial cells. Of the beta-adrenoceptors (ß-ARs), we previously demonstrated the renal expression of ß3-AR in the thick ascending limb (TAL), the distal convoluted tubule (DCT), and the collecting duct (CD), where it participates in salt and water reabsorption. Here, for the first time, we reported ß3-AR expression in the CD intercalated cells (ICCs), where it regulates acid-base homeostasis. Co-localization of ß3-AR with either proton pump H+-ATPase or Cl-/HCO3 - exchanger pendrin revealed ß3-AR expression in type A, type B, non-A, and non-B ICCs in the mouse kidney. We aimed to unveil the possible regulatory role of ß3-AR in renal acid-base homeostasis, in particular in modulating the expression, subcellular localization, and activity of the renal H+-ATPase, a key player in this process. The abundance of H+-ATPase was significantly decreased in the kidneys of ß3-AR-/- compared with those of ß3-AR+/+ mice. In particular, H+-ATPase reduction was observed not only in the CD but also in the TAL and DCT, which contribute to acid-base transport in the kidney. Interestingly, we found that in in vivo, the absence of ß3-AR reduced the kidneys' ability to excrete excess proton in the urine during an acid challenge. Using ex vivo stimulation of mouse kidney slices, we proved that the ß3-AR activation promoted H+-ATPase apical expression in the epithelial cells of ß3-AR-expressing nephron segments, and this was prevented by ß3-AR antagonism or PKA inhibition. Moreover, we assessed the effect of ß3-AR stimulation on H+-ATPase activity by measuring the intracellular pH recovery after an acid load in ß3-AR-expressing mouse renal cells. Importantly, ß3-AR agonism induced a 2.5-fold increase in H+-ATPase activity, and this effect was effectively prevented by ß3-AR antagonism or by inhibiting either H+-ATPase or PKA. Of note, in urine samples from patients treated with a ß3-AR agonist, we found that ß3-AR stimulation increased the urinary excretion of H+-ATPase, likely indicating its apical accumulation in tubular cells. These findings demonstrate that ß3-AR activity positively regulates the expression, plasma membrane localization, and activity of H+-ATPase, elucidating a novel physiological role of ß3-AR in the sympathetic control of renal acid-base homeostasis.
ABSTRACT
Introduction: Solanum aethiopicum L., commonly known as scarlet eggplant (Solanaceae family) is one of the most traditionally cultivated vegetables in Basilicata, a southern region of Italy. Although multiple uses have been given to this vegetable, data about its anti-obesogenic activity are still limited. Methods: This study focuses on testing two different extracts obtained either from the peel or from the whole fruit of the Lucanian Solanum aethiopicum. Their ability to inhibit certain enzymatic activities was tested in vitro and then, the one that showed the better outcomes was tested on an experimental model of High-Fat Diet (HFD) induced obesity. Results: Spectrophotometric assays demonstrated that the peel extract possessed the highest ability to inhibit the selected enzymatic activities and so, its phytochemical profile was obtained through LC-MS chromatography. The oral administration of this extract (25 mg/kg) to HFD-fed mice reduced body weight gain and improved glucose and lipid metabolism. Similarly, the extract ameliorated the obesity-induced inflammatory status by reducing the expression of pro-inflammatory cytokines in both adipose and hepatic tissues. Interestingly, these effects were associated with the improvement of vascular dysfunction. Discussion: Lucanian Solanum aethiopicum extract may represent a new strategic approach for managing obesity and its associated diseases.
ABSTRACT
Obesity is widely associated with intestine barrier impairment, nonalcoholic fatty liver disease (NAFLD) outbreaks, oxidative stress, and inflammation. In a previous investigation, the Solanum aethiopicum L. growing in Basilicata Region has demonstrated to have antioxidant activity; hence this investigation was aimed to evaluate for the first time the antilipidemic and anti-inflammatory activity of the Lucanian S. aethiopicum L. peel extract in vitro on OA-treated HepG2 and Caco-2 cell lines. It was shown that the extract could reduce lipogenesis by down-regulating SREBP-1c and HMGCR expression and fatty acid ß-oxidation by up-regulating PPARα, CPT1A, and UCP2 expression. In addition, the S. aethiopicum L. peel extract might also improve oxidative stress by reducing endoplasmic reticulum stress and regulating the Nrf2 and Nf-κB molecular pathways. Altogether, these results demonstrated for the first time the possible application of the Lucanian S. aethiopicum peel extract for preventing obesity and managing NAFLD.
ABSTRACT
Plant species are a reservoir of natural compounds that can potentially be used to treat different diseases. Citrus medica Linn. belonging to the Rutaceae family, has been used for centuries in medicine for its antioxidant, anti-inflammatory, antimicrobial, antiviral, and antihyperglycemic properties. These activities are ascribable not only to the presence of health-promoting macronutrients and micronutrients, such as carbohydrates, minerals, amino acids, and vitamins, but also to specialized metabolites, such as flavonoids (apigenin, hesperetin, hesperidin, naringin, naringenin, rutin, quercetin, and diosmin), coumarins (citropten, scoparone, and bergapten), terpenes (limonene, γ-terpinene, limonin, and nomilin), and phenolic acids (p-coumaric acid, trans-ferulic acid, and chlorogenic acid). In recent years, particular attention has been focused on the antioxidant, anti-inflammatory, antimicrobial activity, antidiabetic, anticancer, and neuroprotective activity of C. medica. However, although many studies have reported this species' chemical and biological properties, the literature has never been analyzed via a systematic approach. For this reason, using PubMed and Scopus as databases, we performed a systematic review of C. medica's chemical composition and biological properties to inspire new research approaches and increase its curative application.
ABSTRACT
This study evaluates the effect of a chemical fertilizer (ammonium nitrate), a compost (vermicompost from cattle manure) and two biochars (from vine prunings and wood chips, respectively), applied to the soil alone or in mixture, on the yield, phytochemical content and biological activity of Beta vulgaris L. var. cycla (Swiss chard). The respective treatments, each replicated four times, were arranged according to a completely randomized block design. Results showed that vermicompost, both alone and in mixture with vine pruning biochar, significantly increased yield parameters (plant height and leaf area) and yield over the untreated soil and the biochars alone, similar to ammonium nitrate. Moreover, vermicompost, both alone and in mixture, respectively, with the two biochars, determined lower total N and NO3- contents than ammonium nitrate, both alone and in mixture, respectively, with the two biochars. In particular, NO3- content was within the safe thresholds fixed for leafy vegetables by the European Commission to prevent any adverse implication on human health from dietary NO3- exposure. The biochars alone resulted in very low yield and leaf total N content, likely due to a limited release of N for plant uptake, also evidenced by the undetectable NO3- leaf content, similarly shown by plants grown in untreated soil. Vermicompost, alone or in mixture, respectively, with the two biochars, increased the content of specialized metabolites, with a positive effect on antioxidant activity. The organic amendments, particularly compost, could be an alternative to chemical fertilizers to reach a trade-off between yield, nutritional and health qualities in Swiss chard, meeting the needs of farmers and consumers as well as the targets for sustainable food production.
ABSTRACT
Over many years, natural products have been a source of healing agents and have exhibited beneficial uses for treating human diseases. The Gentiana genus is the biggest genus in the Gentianaceae, with over 400 species distributed mainly in alpine zones of temperate countries around the world. Plants in the Gentiana genus have historically been used to treat a wide range of diseases. Still, only in the last years has particular attention been paid to the biological activities of Gentiana lutea Linn., also known as yellow Gentian or bitterwort. Several in vitro/vivo investigations and human interventional trials have demonstrated the promising activity of G. lutea extracts against oxidative stress, microbial infections, inflammation, obesity, atherosclerosis, etc.. A systematic approach was performed using Pubmed and Scopus databases to update G. lutea chemistry and activity. Specifically, this systematic review synthesized the major specialized bitter metabolites and the biological activity data obtained from different cell lines, animal models, and human interventional trials. This review aims to the exaltation of G. lutea as a source of bioactive compounds that can prevent and treat several human illnesses.
Subject(s)
Gentiana , Animals , Humans , Gentiana/chemistry , Gentiana/metabolism , Plant Extracts/pharmacologyABSTRACT
γ-aminobutyric acid (GABA) has several beneficial effects on human health. GABA may be produced via chemical synthesis or through microbial metabolism, and Levilactobacillus brevis is recognized as a GABA-producing species. In this study, 11 Lvb. brevis strains were screened for GABA production, and the best producers were selected to verify the effect of aerobic (AE) and respiratory (RS) cultivations on growth parameters, biomass, and GABA accumulation. Lvb. brevis LB12 was then used to evaluate the combined effect of the incubation atmosphere (anaerobiosis vs. aerobiosis), cell protection (free vs. immobilized cells), and cell recycling (fresh vs. starved cells) on GABA production. Glutamate (GLU) consumption and GABA accumulation were detected by Thin-layer Chromatography (TLC) and RP-HPLC analyses. The ability to produce GABA was widespread among the strains. AE and RS growth improved biomass production, but oxygen availability impaired GLU to GABA conversion, and the anaerobically growing cells had the highest GABA productivity. Immobilized strains had lower efficiency in both GLU uptake and conversion compared to free cells, probably due to the poor diffusion in alginate beads. The use of resting cells allowed further GABA production without the cultivation step, but cell activity was exhausted after three cycles of reutilization. Lvb. brevis LB12 is an excellent GABA producer, and AE cultivation can be exploited to improve the final cell density; however, the conditions for boosting GLU to GABA conversion and cell regeneration need to be further investigated.
ABSTRACT
The present study investigated the potential antioxidant applications of Humulus lupulus L. as raw extract and nanoformulated in liposomes. H. lupulus is commonly used as a food ingredient, but it is also a promising source of specialized metabolites with health-promoting effects. In the extract obtained by hydroalcoholic maceration, 24 compounds were characterized using liquid chromatography-mass spectrometry analyses. The extract exhibited an interesting antioxidant activity in in vitro spectrophotometric and cell assays. The extract was nanoformulated into liposomes to exploit and improve its beneficial proprieties. The in vitro assays revealed that, after incorporation into liposomes, the extract's antioxidant activity was preserved and even improved. Moreover, a lower dose of the extract was required to prevent reactive oxygen species overproduction when included in the nanoformulation. These results confirm the advantages of nanoformulating herbal extract to maximize its health-promoting effects for a potential pharmaceutical application.
Subject(s)
Humulus , Antioxidants/chemistry , Chromatography, Liquid , Humulus/chemistry , Liposomes , Plant Extracts/chemistryABSTRACT
Food extract's biological effect and its improvement using nanotechnologies is one of the challenges of the last and the future decades; for this reason, the antioxidant effect of scarlet eggplant extract liposomal incorporation was investigated. Scarlet eggplant (Solanum aethiopicum L.) is a member of the Solanaceae family, and it is one of the most consumed vegetables in tropical Africa and south of Italy. This study investigated the antioxidant activity and the phytochemical composition of S. aethiopicum grown in the Basilicata Region for the first time. The whole fruit, peel, and pulp were subjected to ethanolic exhaustive maceration extraction, and all extracts were investigated. The HPLC-DAD analysis revealed the presence of ten phenolic compounds, including hydroxycinnamic acids, flavanones, flavanols, and four carotenoids (one xanthophyll and three carotenes). The peel extract was the most promising, active, and the richest in specialized metabolites; hence, it was tested on HepG2 cell lines and incorporated into liposomes. The nanoincorporation enhanced the peel extract's antioxidant activity, resulting in a reduction of the concentration used. Furthermore, the extract improved the expression of endogenous antioxidants, such as ABCG2, CAT, and NQO1, presumably through the Nrf2 pathway.
ABSTRACT
Dittrichia graveolens L. Greuter belonging to the Asteraceae family, is an aromatic herbaceous plant native to the Mediterranean region. This plant species has been extensively studied for its biological activities, including antioxidant, antitumor, antimicrobial, antifungal, anti-inflammatory, anticholinesterase, and antityrosinase, and for its peculiar metabolic profile. In particular, bioactivities are related to terpenes and flavonoids metabolites, such as borneol (40), tomentosin (189), inuviscolide (204). However, D. graveolens is also well known for causing health problems both in animals and humans. Moreover, the species is currently undergoing a dramatic northward expansion of its native range related to climate change, now including North Europe, California, and Australia. This review represents an updated overview of the 52 literature papers published in Scopus and PubMed dealing with expansion, chemistry (262 different compounds), pharmacological effects, and toxicology of D. graveolens up to October 2021. The review is intended to boost further studies to determine the molecular pathways involved in the observed activities, bioavailability, and clinical studies to explore new potential applications.
Subject(s)
Asteraceae/chemistry , Flavonoids/chemistry , Flavonoids/pharmacology , Terpenes/chemistry , Terpenes/pharmacology , Animals , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Drug Discovery , Humans , Plant Extracts/chemistry , Plant Extracts/pharmacologyABSTRACT
For centuries, natural medicines have represented the only option for treating human diseases and, nowadays, plant phytochemicals are considered as promising compounds to treat or prevent chronic conditions. Among them, hop flowers (Humulus lupulus L.), typically used in brewing industries to give the typical aroma and flavor to beer, have attracted particular attention for their health promoting properties. Several in vivo/vitro studies and human interventional trials have demonstrated the beneficial effects of these molecules on weight gain, lipid metabolism, glucose homeostasis, insulin sensitivities, and inflammation by acting on different targets. All these activities suggest a possible role of bitter hop acid in preventing metabolic syndrome and its related diseases. A systematic quest on PubMed and Scopus databases was performed to identify pre-clinical and clinical studies focusing on this topic. This systematic review summarizes the results obtained by different cell lines, animal models, and human interventional trials to propose iso-α-acids as medical nutrition therapy to treat or prevent metabolic syndrome and its related disorders as diabetes, dislipidemia inflammation, etc.