Sceletium tortuosum (L.) N.E.Br, the most sought after and widely researched species in the genus Sceletium is a succulent forb endemic to South Africa. Traditionally, this medicinal plant is mainly ...masticated or smoked and used for the relief of toothache, abdominal pain, and as a mood-elevator, analgesic, hypnotic, anxiolytic, thirst and hunger suppressant, and for its intoxicating/euphoric effects. Sceletium tortuosum is currently of widespread scientific interest due to its clinical potential in treating anxiety and depression, relieving stress in healthy individuals, and enhancing cognitive functions. These pharmacological actions are attributed to its phytochemical constituents referred to as mesembrine-type alkaloids.
The aim of this review was to comprehensively summarize and critically evaluate recent research advances on the phytochemistry, pharmacokinetics, biological and clinical activities of the medicinal plant S. tortuosum. Additionally, current ongoing research and future perspectives are also discussed.
All relevant scientific articles, books, MSc and Ph.D. dissertations on botany, behavioral pharmacology, traditional uses, and phytochemistry of S. tortuosum were retrieved from different databases (including Science Direct, PubMed, Google Scholar, Scopus and Web of Science). For pharmacokinetics and pharmacological effects of S. tortuosum, the focus fell on relevant publications published between 2009 and 2021.
Twenty-five alkaloids belonging to four structural classes viz: mesembrine, Sceletium A4, joubertiamine, and tortuosamine, have been identified from S. tortuosum, of which the mesembrine class is predominant. The crude extracts and commercially available standardized extracts of S. tortuosum have displayed a wide spectrum of biological activities (e.g. antimalarial, anti-oxidant, immunomodulatory, anti-HIV, neuroprotection, enhancement of cognitive function) in in vitro or in vivo studies. This plant has not yet been studied in a clinical population, but has potential for enhancing cognitive function, and managing anxiety and depression.
As an important South African medicinal plant, S. tortuosum has garnered many research advances on its phytochemistry and biological activities over the last decade. These scientific studies have shown that S. tortuosum has various bioactivities. The findings have further established the link between the phytochemistry and pharmacological application, and support the traditional use of S. tortuosum in the indigenous medicine of South Africa.
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•Sceletium tortuosum is the most widely researched species in the genus Sceletium.•This is due to its potential to treat different central nervous system disorders.•Mesembrine alkaloids are considered the major chemical- and biomarkers.•This review provides a comprehensive update on research advances of S. tortuosum.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Fragile X syndrome, the main cause of inherited mental retardation, is caused by transcriptional silencing of the fragile X mental retardation gene, FMR1. Absence of the associated protein FMRP leads ...to the dysregulation of many genes creating a phenotype of ADHD, anxiety, epilepsy and autism. The core aim of this review is to summarise two decades of molecular research leading to the characterisation of cellular and molecular pathways involved in the pathology of this disease and as a consequence to the identification of two new promising targets for rational therapy of fragile X syndrome, namely the group 1 metabotrope glutamate receptors (Gp1 mGluRs) and the gamma-amino butyric acid A receptors (GABA(A)Rs). As no current clinical treatments are directed specifically at the underlying neuronal defect due to absence of FMRP, this might open new powerful therapeutic strategies.
Repair of articular cartilage defects using tissue engineered constructs composed of a scaffold and cultured autologous cells holds promise for future treatments. However, nutrient limitation (e.g. ...oxygen) has been suggested as a cause of the onset of chondrogenesis solely within the peripheral boundaries of larger constructs.
In the present study, oxygen gradients were evaluated by microelectrode measurements in two porous polyethylene glycol terephthalate/polybutylene terephthalate (PEGT/PBT) scaffold architectures, a compression-molded and particle-leached sponge (CM) and a 3D-deposited fiber (3DF) scaffold.
During the first 14 days in vitro, gradients intensified, after which a gradual decrease of the gradients was observed in vitro. In vivo, however, gradients changed instantly and became less pronounced. Although similar gradients were observed regardless of scaffold type, significantly more cells were present in the center of 3DF constructs after 2 weeks of in vivo culture.
Our results stress the importance of a rationally designed scaffold for tissue-engineering applications. Organized structures, such as the 3DF PEGT/PBT polymer scaffolds, offer possibilities for regulation of nutrient supply and, therefore, hold promise for clinical approaches for cartilage repair.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A major flaw in autism spectrum disorder (ASD) management is late diagnosis. Activity-dependent neuroprotective protein (ADNP) is a most frequent de novo mutated ASD-related gene. Functionally, ADNP ...protects nerve cells against electrical blockade. In mice, complete Adnp deficiency results in dysregulation of over 400 genes and failure to form a brain. Adnp haploinsufficiency results in cognitive and social deficiencies coupled to sex- and age-dependent deficits in the key microtubule and ion channel pathways. Here, collaborating with parents/caregivers globally, we discovered premature tooth eruption as a potential early diagnostic biomarker for ADNP mutation. The parents of 44/54 ADNP-mutated children reported an almost full erupted dentition by 1 year of age, including molars and only 10 of the children had teeth within the normal developmental time range. Looking at Adnp-deficient mice, by computed tomography, showed significantly smaller dental sacs and tooth buds at 5 days of age in the deficient mice compared to littermate controls. There was only trending at 2 days, implicating age-dependent dysregulation of teething in Adnp-deficient mice. Allen Atlas analysis showed Adnp expression in the jaw area. RNA sequencing (RNAseq) and gene array analysis of human ADNP-mutated lymphoblastoids, whole-mouse embryos and mouse brains identified dysregulation of bone/nervous system-controlling genes resulting from ADNP mutation/deficiency (for example, BMP1 and BMP4). AKAP6, discovered here as a major gene regulated by ADNP, also links cognition and bone maintenance. To the best of our knowledge, this is the first time that early primary (deciduous) teething is related to the ADNP syndrome, providing for early/simple diagnosis and paving the path to early intervention/specialized treatment plan.
Intellectual disability (ID), characterized by an intellectual performance of at least 2 SD (standard deviations) below average is a frequent, lifelong disorder with a prevalence of 2–3%. Today, only ...for at most half of patients a diagnosis is made. Knowing the cause of the ID is important for patients and their relatives, as it allows for appropriate medical care, prognosis on further development of the disorder, familial counselling or access to support groups. Whole‐exome sequencing (WES) now offers the possibility to identify the genetic cause for patients for which all previously available genetic tests, including karyotyping, specific gene analysis, or microarray analysis did not reveal causative abnormalities. However, data analysis of WES experiments is challenging. Here we present an analysis workflow implementable in any laboratory, requiring no bioinformatics knowledge. We demonstrated its feasibility on a cohort of 10 patients, in which we found a conclusive diagnosis in 3 and a likely diagnosis in 2 more patients. Of the three conclusive diagnoses, one was a clinically suspected mutation missed by Sanger sequencing, and one was an atypical presentation of a known monogenic disorder, highlighting two essential strengths of WES‐based diagnostics.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Cannabis sativa is a well-known recreational drug and, as such, a controlled substance of which possession and use are illegal in most countries of the world. Due to the legal constraints on the ...possession and use of C. sativa, relatively little research on the medicinal qualities of this plant has been conducted. Interest in the medicinal uses of this plant has, however, increased in the last decades. The methods of administration for medicinal purposes are mainly through oral ingestion, smoking, and nowadays also inhalation through vaporization. During this study the commercially available Volcano vaporizing device was compared with cannabis cigarette smoke. The cannabis smoke and vapor (obtained at different temperatures) were quantitatively analyzed by high-performance liquid chromatography (HPLC). In addition, different quantities of cannabis material were also tested with the vaporizer. The cannabinoids:by-products ratio in the vapor obtained at 200°C and 230°C was significantly higher than in the cigarette smoke. The worst ratio of cannabinoids:by-products was obtained from the vaporized cannabis sample at 170°C.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
MicroRNAs (miRNAs) are small non-coding RNAs that inhibit expression of specific target genes at the posttranscriptional level. MiRNAs are often found to be misregulated in human cancer, and they can ...act as either potent oncogenes or tumour suppressor genes. Here we show that a germline mutation in mature miR-125a is highly associated with breast cancer tumorigenesis, suggesting that miR-125a is likely to function as a tumour suppressor gene in human cancer.
With increasing use of herbal medicines for chronic or serious illness, relevant quality assurance methods are essential for making claims of therapeutic benefit. Adequate demonstration of safety and ...efficacy based on chemical composition and ensuring consistency between manufactured batches is critical. To date, there has been no uniform standard approach or detailed framework provided to industry for selecting relevant chemical markers used to standardize herbal products. We developed the Herbal Marker Ranking System (Herb MaRS) providing guidance on prioritizing the selection of chemical markers for quality control of complex multi‐herb mixtures, while also taking into account the bioactivity in relation to the symptoms of the disease and its concentration in the formula. We apply the Herb MaRS evaluation criteria to a seven‐herb formulation for the treatment of irritable bowel syndrome with constipation. Our ranking scale accommodates the clinical and pharmacological use of the formulation and its claimed indications.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The genus Artemisia consists of about 500 species, occurring throughout the world. Some very important drug leads have been discovered from this genus, notably artemisinin, the well known ...anti-malarial drug isolated from the Chinese herb Artemisia annua. The genus is also known for its aromatic nature and hence research has been focussed on the chemical compositions of the volatile secondary metabolites obtained from various Artemisia species. In the southern African region, A. afra is one of the most popular and commonly used herbal medicines. It is used to treat various ailments ranging from coughs and colds to malaria and diabetes. Although it is one of the most popular local herbal medicines, only limited scientific research, mainly focussing on the volatile secondary metabolites content, has been conducted on this species. The aim of this review was therefore to collect all available scientific literature published on A. afra and combine it into this paper. In this review, a general overview will be given on the morphology, taxonomy and geographical distribution of A. afra. The major focus will however be on the secondary metabolites, mainly the volatile secondary metabolites, which have been identified from this species. In addition all of the reported biological activities of the extracts derived from this species have been included as well as the literature on the pharmacology and toxicology. We aim at bringing together most of the available scientific research conducted on this species, which is currently scattered across various publications, into this review paper.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP