Qat (Catha edulis)

Resumen Context: Consumption of khat leaves has been disseminated worldwide with the migration of its users from Arabia and Africa. Despite numerous reports regarding the associations of khat chewing with serious health impacts, a significant number of people worldwide uses khat daily, especially in its origin countries. The risk of coadministration of khat and drugs (prescription and over the-counter medications) is high among these individuals, leading to increase probability of adverse khat-drug interactions. The likelihood of khatdrug interactions could be higher than drug-drug interactions because drugs usually contain single chemical entities while almost all herbs (including khat) contain mixtures of pharmacologically active constituents. Aims: To review the literatures on how khat interacts with some drugs and whether it is favorable or not. Methods: The study was conducted as a systematic review. The electronic literature searches were made in Google search engine to access...

Background: Khat (Catha edulis Forsk) leaves are chewed by people in certain regions of East Africa and the Middle East for their stimulating amphetamine-like effects. The purpose of this scoping review is to systematically map the current in vitro publications that investigated the toxicological potential effects of khat on cultured human or animal cells in terms of cellular viability and activity. Methods: A comprehensive electronic database search was undertaken up to December 2020 without starting date or language restrictions in accordance with the PRISMA extension for scoping review guideline and methodological quality evaluation based on the guidelines for reporting pre-clinical in vitro studies on dental materials. All in vitro studies that investigated the effect of khat plant extract (Catha Edulis) on the cultured human or animal cells were included. Results: The initial search yielded 599 articles and 16 articles were finally selected to be included. The treatment of cells with khat produced different degrees of cellular changes, including decreased cellular survival, induction of apoptosis, increased ROS production, alteration of cell phenotype, and of arrest cell cycle. In this contest, khatexposed cells expressed higher levels of pro-apoptotic protein Bax and lower levels of anti-apoptotic Bcl-2, upregulated p38, p53, p16, and p21 proteins, as well as premature expression of differentiation markers. Conclusion: Based on the current scoping review, khat induced apoptosis and cytotoxicity in cultured human cells, including oral cells.

Traditionally, the leaves of Catha edulis Forsskal (Khat) are consumed by the people of Yemen primarily for its recreational effect, and secondarily, for achieving certain tasks. Additionally, Yemeni diabetics chew such leaves in the belief that this can control their elevated blood glucose level. This review focuses on outlining the findings of studies that have been conducted to display the glycemic effect of Catha edulis, while trying to balance it with findings of the association of its chewing with the development of type 2 diabetes mellitus (DM). The search strategy adopted was based on a comprehensive research in Medline, PubMed, Web of Science, JSTOR, Scopus and Cochrane for articles, proceeding abstracts and theses to identify complete reports written in the English language about the glycemic effect of Catha edulis in humans and animals from 1976 to 2016. In addition, bibliographies were also reviewed to find additional reports not otherwise published. Thirty seven records were identified of which, 25 eligible studies were included in the meta­analysis using blood glucose as an outcome measurement. Studies were divided into four subgroups according to the experimental model, namely; non­diabetic animals, diabetic animals, non­diabetic humans and diabetic humans. The pooled mean difference (MD) of blood glucose between experimental and control were calculated using random effects model of the weighted mean difference of blood glucose with 95% confidence interval (CI). Heterogeneity between studies was tested using I(2) statistic and a value of P<0.05 was considered to indicate statistical significance.

Khat (Catha edulis (Vahl) Endl.) is an evergreen flowering shrub used as a stimulant in many regions worldwide including East Africa, the Arabian Peninsula, Europe, and the United States. Chewing leaves of khat induces excitement and euphoria, which are primarily attributed to two major constituents, cathinone and cathine. Khat also contains other important constituents such as cathedulins. A considerable number of studies reported side effects induced by the khat extracts to both embryos and adults. These include teratogenicity and developmental retardation, oral cancer and ulcers, high blood pressure, and myocardial infarction. So far, little attention has been paid to the effects of khat extracts on the molecular signaling interactions. We aimed in this study to investigate this through evaluating the effects of khat extracts on SKOV3, a human ovarian adenocarcinoma cell line. We show, by in vitro assays, that khat induces several cellular defects including reduced cell size, cell membrane damage, and apoptosis. At high khat extract concentrations, the cell metabolic activity, cell cycle, and cellular proliferation were affected. RT-qPCR analysis showed an increase in the gene expression of the apoptotic marker BAX, the tumor suppressor p53, and the inflammatory cytokine IL-6. Protein expression analysis by immunostaining showed downregulation of β-catenin, E-cadherin, and Ki-67 and upregulation of FZD8 and SPRY2, suggesting that Wnt and FGF signaling were implicated. SwissTargetPrediction in silico analysis showed that khat constituents cathine, cathinone, catheduline K2, and catheduline E5 bind to family A G-protein-coupled receptor, cause many neurological diseases and disorders such as Alzheimer’s, schizophrenia, depression, and anxiety, and induce many ovarian cancer related diseases. The analysis also showed that important signaling pathways such as CREB, Wnt, FGF, IL-6, and ERK/MAPK, and that of the endometrial cancer, and cell cycle were implicated. Upstream regulators of cathine and cathinone were found to potentially target several molecules including interleukin-8, MMP2, PLAU, and micro-RNAs. In conclusion, khat induces significant cellular and molecular changes that could potentially cause a wide range of serious diseases and syndromes. Such an impact could have a heavy burden on the health care system in the countries where khat is consumed.

Objectives: The relative importance of risk factors of periodontitis varies from one population to another. In this study, we sought to identify independent risk factors of periodontitis in a Yemeni population.

Methods: One hundred and fifty periodontitis cases and 150 healthy controls, all Yemeni adults 30-60years old, were recruited. Sociodemographic data and history of oral hygiene practices and oral habits were obtained. Plaque index (PI) was measured on index teeth. Periodontal health status was assessed using Community Periodontal Index (CPI) and Clinical Attachment Loss (CAL) according to WHO. Periodontitis was defined as having one or more sextants with a CPI score3. Multiple logistic regression modelling was employed to identify distal, intermediate and proximal determinants of periodontitis, while ordinal regression was used to identify those of CAL scores.

Results: In logistic regression, PI score was associated with the highest odds of periodontitis (OR = 82.9) followed by cigarette smoking (OR = 12.8), water pipe smoking (OR = 10.2), male gender (OR = 3.4) and age (OR = 1.19); on the other hand, regular visits to the dentist (OR = 0.05), higher level of education (OR = 0.37) and daily dental flossing (OR = 0.95) were associated with lower odds. Somewhat similar associations were seen for CAL scores (ordinal regression); however, qat chewing was identified as an additional determinant (OR = 4.69).

Conclusion: Water pipe smoking is identified as a risk factor of periodontitis in this cohort in addition to globally known risk factors. Adjusted effect of qat chewing is limited to CAL scores, suggestive of association with recession.