Chemical composition, seasonal variation and antiaging activities of essential oil from Callistemon subulatus leaves growing in Egypt

Anti-inflammatory activity of d-pinitol possibly through inhibiting COX-2 enzyme: in vivo and in silico studies

Introduction: D-pinitol, a naturally occurring inositol, has diverse biological activities like antioxidant, antimicrobial and anticancer activities. This study aimed to evaluate anti-inflammatory effect of d-pinitol in a chick model. Additionally, in silico studies were performed to evaluate the molecular interactions with cyclooxygenase-2 (COX-2). Methods: The tested groups received d-pinitol (12.5, 25, and 50 mg/kg) and the standard drugs celecoxib and ketoprofen (42 mg/kg) via oral gavage prior to formalin injection. Then, the number of licks was counted for the first 10 min, and the paw edema diameter was measured at 60, 90, and 120 min. Results and Discussion: The d-pinitol groups significantly (p < 0.05) reduced the number of paw licks and paw edema diameters, compared to negative control. When d-pinitol was combined with celecoxib, it reduced inflammatory parameters more effectively than the individual groups. The in silico study showed a promising binding capacity of d-pinitol with COX-2. Taken together, d-pinitol exerted anti-inflammatory effects in a dose-dependent manner, possibly through COX-2 interaction pathway.

Variation of the essential oil components of Citrus aurantium leaves upon using different distillation techniques and evaluation of their antioxidant, antidiabetic, and neuroprotective effect against Alzheimer's disease

Citrus fruit essential oil is considered one of the widely studied essential oils while its leaves attract less attention although being rich in nearly the same composition as the peel and flowers. The leaves of bitter orange or sour orange (Citrus aurantium L.) were extracted using three different techniques namely; hydrodistillation (HD), steam distillation (SD), and microwave-assisted distillation (MV) to compare their chemical composition. The three essential oil samples were analyzed through GC/FID and GC/MS analyses. The samples were tested in vitro using different antioxidant techniques (DPPH, ABTS, CUPRAC, FRAP, PBD, and MCA), neuroprotective enzyme inhibitory activities (acetylcholine and butyl choline enzymes), and antidiabetic activities (α-amylase and α-glucosidase). The results showed that thirty-five volatile ingredients were detected and quantified. Monoterpenes represented the most abundant class in the three essential oils followed by sesquiterpenes. C. aurantium essential oil carried potential antioxidant activity where SD exhibited the highest antioxidant activity, with values arranged in the following order: FRAP (200.43 mg TE/g), CUPRAC (138.69 mg TE/g), ABTS (129.49 mg TE/g), and DPPH (51.67 mg TE/g). SD essential oil also presented the most potent α-amylase (0.32) inhibition while the MV essential oil showed the highest α-glucosidase inhibition (2.73 mmol ACAE/g), followed by HD (2.53 mmol ACAE/g), and SD (2.46 mmol ACAE/g). The SD essential oil exhibited the highest BChE and AChE inhibitory activities (3.73 and 2.06 mg GALAE/g), respectively). Thus, bitter orange essential oil can act as a potential source of potent antioxidant, antidiabetic, and neuroprotective activities for future drug leads.

Polysaccharides (pectin, mucilage, and fructan inulin) and their fermented products: A critical analysis of their biochemical, gut interactions, and biological functions as antidiabetic agents

Diabetes mellitus is a globally metabolic endocrine syndrome marked by a deficiency of insulin secretion (type-1 DM) or glucose intolerance arising from insulin response impairment (type-2 DM) leading to abnormal glucose metabolism. With an increasing interest in natural dietary components for diabetes management, the identification of novel agents witnessed major discoveries. Plant-derived mucilage, pectin, and inulin are important non-starch polysaccharides that exhibit effective antidiabetic properties often termed soluble dietary fiber (SDF). SDF affects sugar metabolism through multiple mechanisms affecting glucose absorption and diffusion, modulation of carbohydrate metabolizing enzymes (α-amylase and α-glucosidase), ameliorating β-pancreatic cell dysfunction, and improving insulin release or sensitivity. Certain SDFs inhibit dipeptidyl peptidase-4 and influence the expression levels of genes related to glucose metabolism. This review is designed to discuss holistically and critically the antidiabetic effects of major SDF and their underlying mechanisms of action. This review should aid drug discovery approaches in developing novel natural antidiabetic drugs from SDF.

Role of Nutraceuticals in Obesity Management: A Mechanism and Prospective Supported by Molecular Docking Studies

Obesity and its comorbidities represent a major health problem worldwide. Treatment by reducing food intake and physical activity interventions has limited success especially with elderly people with chronic diseases. Nutraceuticals are naturally originated and successfully used for their physiological and nutritional benefit in health care. They might be alternative means to help lose weight and reduce obesity-associated metabolic disorders with the improvement of health, delay the aging process, prevention of chronic diseases, increase of life expectancy, or support to the structure or function of the body. The current study enumerates the inherent role of nutraceuticals in the management of obesity and its related comorbidities. The study is supported with the molecular docking studies discussing the mechanism of action. An attempt to optimize the role of nutraceuticals is made in this article in addition to widen the scope of its use in this chronic worldwide disease.

In Vitro Antioxidant and In Vivo Hepatoprotective Properties of Wissadula periplocifolia Extract

Wissadula periplocifolia (L.) Thwaites is a traditional medicinal plant belonging to the family Malvaceae, used in folk medicine for inflamed snake bites and bee stings. The current study was designed to investigate the in vitro antioxidant and in vivo anti-inflammatory and hepatoprotective activities of 80% ethanol extract of W. periplocifolia and its different fractions. The crude ethanolic extract (CEE) was then serially fractionated with petroleum ether fraction (PEF), chloroform fraction (CHF), and aqueous fraction (AQF). The antioxidant activity was assessed using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay, anti-inflammatory activity was determined in the xylene-induced ear edema model, and hepatoprotective activity was measured in the paracetamol-induced hepatic injury model. PEF showed a significant scavenging effect with an IC50 value of 33.5 μg/mL, followed by CEE (IC50 = 42.2 μg/mL), CHF (IC50 = 77 μg/mL), and AQF (IC50 = 80 μg/mL), compared to standard butylated hydroxytoluene (IC50 = 14.8 μg/mL). Both doses of CEE (250 and 500 mg/kg) could reduce ear edema by 41.3 and 50%, respectively, compared to standard diclofenac sodium (76.09%). Moreover, CEE significantly reduces the elevated liver enzymes (ALT, AST, and ALP), compared to control. Nevertheless, it elevated blood protein and reduced the blood bilirubin level (p < 0.01), compared to control. Histopathological studies also indicated significant protection of the liver from paracetamol-induced liver damage. In conclusion, W. periplocifolia could be a good source of antioxidant and hepatoprotective phytochemicals; meanwhile, toxicological and pharmacokinetic studies are recommended.

Genus Pimenta: An Updated Comprehensive Review on Botany, Distribution, Ethnopharmacology, Phytochemistry and Biological Approaches

Pimenta is a genus of flowering plants belonging to family Myrtaceae, native to the West Indies, Mexico, and South America. Numerous traditional uses were reported as anti-inflammatory, analgesic, antipyretic, sedative, diuretic, and sexual stimulant. This article aims to provide a comprehensive overview of the botany, traditional uses, phytochemical profile, and biological activities of genus Pimenta for future exploration of plant-based drugs and therapeutic approaches. The data were collected (up to date as of October 1, 2023) from several databases such as Web of Science, google scholar, science direct, Pubmed and Proquest. Pimenta species were reported to include various classes of phytochemicals like tannins, saponins, flavonoids, phenylpropanoids, monoterpenes, sesquiterpenes and essential oils. Quercetin glycosides and eugenol derivatives were the predominant compounds of this genus. Several biological activities have been reported such as antihypertensive, antioxidant, antimicrobial, antiviral, histidine decarboxylase inhibition, hypoglycemic, anticancer, anti-inflammatory, analgesic, antipyretic, acaricidal, anxiolytic, anti-depressant and anti-estrogenic. Several scientific reports have been published on various isolated phytochemicals and pharmacological properties of Pimenta species that confirm its ethnobotanical and traditional history. However, in vivo studies on different extracts and their phytoconstituents, alongside mechanistic analysis deserve more attention for drug researchers to provide better guidance to utilize Pimenta plants as medicinal resources for herbal formulations in different approaches.

The efficacy of natural bioactive compounds against prostate cancer: Molecular targets and synergistic activities

Globally, prostate cancer (PCa) is regarded as a challenging health issue, and the number of PCa patients continues to rise despite the availability of effective treatments in recent decades. The current therapy with chemotherapeutic drugs has been largely ineffective due to multidrug resistance and the conventional treatment has restricted drug accessibility to malignant tissues, necessitating a higher dosage resulting in increased cytotoxicity. Plant-derived bioactive compounds have recently attracted a great deal of attention in the field of PCa treatment due to their potent effects on several molecular targets and synergistic effects with anti-PCa drugs. This review emphasizes the molecular mechanism of phytochemicals on PCa cells, the synergistic effects of compound-drug interactions, and stem cell targeting for PCa treatment. Some potential compounds, such as curcumin, phenethyl-isothiocyanate, fisetin, baicalein, berberine, lutein, and many others, exert an anti-PCa effect via inhibiting proliferation, metastasis, cell cycle progression, and normal apoptosis pathways. In addition, multiple studies have demonstrated that the isolated natural compounds: d-limonene, paeonol, lanreotide, artesunate, and bicalutamide have potential synergistic effects. Further, a significant number of natural compounds effectively target PCa stem cells. However, further high-quality studies are needed to firmly establish the clinical efficacy of these phytochemicals against PCa.

Phytochemical profiling and neuroprotective activity of Callistemon subulatus leaves against cyclophosphamide-induced chemobrain

Cyclophosphamide (CPA) is a chemotherapeutic drug used for various types of cancers. However, patients receiving CPA for long periods suffer cognitive impairment associated with difficulties in learning, decreased concentration, and impaired memory. Chemotherapy-induced cognitive impairment, known as chemobrain, has been attributed to enhanced oxidative stress and inflammatory response. The current study aimed to identify the phytoconstituents of Callistemon subulatus extract (CSE) using HPLC-ESI/MS-MS analysis and evaluate its neuroprotective activity against CPA-induced chemobrain in rats. Fourteen compounds were identified following HPLC analysis including, five phlorglucinols, four flavonol glycosides, a triterpene, and a phenolic acid. Forty rats were divided into five groups treated for ten days as follows; group I (control group), group II received CPA (200 mg/kg, i.p.) on the 7th day, groups III and IV received CSE (200 and 400 mg/kg respectively, orally) for ten days and CPA (200 mg/kg, i.p.) on the 7th day, and group V received only CSE (400 mg/kg, orally) for ten days. The administration of CSE effectively ameliorated the deleterious effects of CPA on spatial and short-term memories, as evidenced by behavioral tests, Y-maze and passive avoidance. Such findings were further confirmed by histological examination. In addition, CSE counteracted the effect of CPA on hippocampal acetylcholinesterase (AChE) activity enhancing the level of acetylcholine. Owing to the CSE antioxidant properties, it hindered the CPA-induced redox imbalance, which is represented by decreased catalase and reduced glutathione levels, as well as enhanced lipid peroxidation. Therefore, CSE may be a promising natural candidate for protection against CPA-induced chemobrain in cancer patients.

Anticancer Potential of the Plant-Derived Saponin Gracillin: A Comprehensive Review of Mechanistic Approaches

With the increasing prevalence of cancer and the toxic side effects of synthetic drugs, natural products are being developed as promising therapeutic approaches. Gracillin is a naturally occurring triterpenoid steroidal saponin with several therapeutic activities. It is obtained as a major compound from different Dioscorea species. This review was designated to summarize the research progress on the anti-cancer activities of gracillin focusing on the underlying cellular and molecular mechanisms, as well as its pharmacokinetic features. The data were collected (up to date as of May 1, 2023) from various reliable and authentic literatures comprising PubMed, Springer Link, Scopus, Wiley Online, Web of Science, ScienceDirect, and Google Scholar. The findings demonstrated that gracillin displays promising anticancer effects through various molecular mechanisms, including anti-inflammatory effects, apoptotic cell death, induction of oxidative stress, cytotoxicity, induction of genotoxicity, cell cycle arrest, anti-proliferative effect, autophagy, inhibition of glycolysis, and blocking of cancer cell migration. Additionally, this review highlighted the pharmacokinetic features of gracillin, indicating its lower oral bioavailability. As a conclusion, it can be proposed that gracillin could serve as a hopeful chemotherapeutic agent. However, further extensive clinical research is recommended to establish its safety, efficacy, and therapeutic potential in cancer treatment.