Pharmacological and Toxicological Effects of Catha edulis F. (Khat)

Khat consumption and undernutrition among adult population in Ethiopia: A systematic review and meta-analysis

BACKGROUND

In Ethiopia, malnutrition is a public health threat causing a significant burden of morbidity, mortality, and economic crisis. Simultaneously, khat consumption is alarmingly increasing among adults, yet it might contribute to the existing burden of malnutrition, where the current evidence is inconclusive. Hence, this review was to estimate the association between khat consumption and undernutrition among adults in Ethiopia.

METHODS

A comprehensive search for Google, Google Scholar, and PubMed, coupled with a thorough manual search of the literature, was done up to date, October 18, 2023, using relevant search terms: "impact," "effects," "khat chewing," "khat consumption," "Ethiopia," "nutritional status," and "undernutrition." An updated PRISMA guideline was used to select relevant literature. The extracted data was summarized in narrative summaries, descriptions, and meta-analyses. The risk of bias was assessed. The results are presented in forest plots and funnel plots to assess publication bias. A pooled effect size (odds ratio) with a 95% certainty level was reported.

RESULTS

While a total of 17 articles (n = 45,679) were included in the narrative review, only 15 articles were included in the quantitative meta-analysis. The majority of studies had a low and moderate risk of bias (based on risk of bias assessment tool), mainly due to unclear exposure assessment and high study heterogeneity. A total of 11 studies were cross-sectional studies (71%), three were comparative studies (17.4%), and three were case control studies (17.4%). There is a higher risk of publication bias as evidenced by the funnel plot. Overall, five studies were from the Oromia region, and three studies were conducted at the national level. Overall, chewing had been shown to significantly increase the risk of undernutrition by 53% (pooled OR = 1.53; 95% CI: 1.09-2.16) under a random effect model. Under the fixed effect model, higher weight was given to national-level studies with higher samples, where chewing contributed to a 12% increased risk of undernutrition (AOR = 1.12; 95% CI: 1.01-2.23). Hence, khat chewing could raise the odds of undernutrition by 12-53%.

CONCLUSION

There is evidence of an association between khat chewing and an increased risk of undernutrition among adults in Ethiopia, which highlights the need for public health interventions to address the potential adverse effects of khat chewing on nutritional status.

Determinants of undernutrition among khat chewing and non-khat chewing male adults in Addis Ababa, Ethiopia: a comparative cross-sectional study

Khat chewing is a deep-rooted socio-cultural tradition that affects appetite, gastric emptying, and food intake, ultimately influencing nutritional status. Moreover, there is significant variation in lifestyles and ways of living among khat chewing and non-chewing people. However, there is limited evidence on the disaggregated determinants of undernutrition among khat chewers and non-chewers in Ethiopia. A community-based comparative cross-sectional study was conducted with 253 Khat-chewing and 249 non-chewing male adults in Addis Ababa, Ethiopia. Weight and height were measured under standard procedure and used to calculate the body mass index (BMI < 18.5 kg/m2 indicates undernutrition). Variables with p-values below 0.25 in the bi-variable analysis were entered into a multivariable logistic regression model to identify factors associated with undernutrition and to control confounding respectively. An adjusted odds ratio with 95% confidence interval was used to declare the presence and the strength of association between the independent and outcome variable. Statistical significance was declared at a p value of 0.05. In this study, a total of 138 (27.5%: 23.6-31.6%) adult males were undernourished; among them, 78 (32.0%) were khat chewers and 60 (23.9%) were non chewers. Christian religion (AOR = 1.49; 1.02-2.30), vegetable consumption (AOR = 1.69; 95% CI 1.12-2.55) and khat chewing (AOR = 1.60; 1.04-2.45) were independent risk factors for undernutrition. However, none of the above factors showed a statistically significant association among non-khat chewer male adults. In conclusion, undernutrition was a public health concern in male adults in the study area. Frequent consumption of fruits, vegetables and family size of the households were the independent predictors of undernutrition. The practical implication of identifying risk factors of undernutrition among chewers and non-chewers could be helpful in depicting the relevant risk factors by exposure category and helping to further refine intervention packages. In addition, focusing on interventions which can increase the availability and accessibility of fruits and vegetables are important to improve the nutritional status of adult male populations.

Congenital anomalies and risk factors in Africa: a systematic review and meta-analysis

OBJECTIVE

To evaluate the pooled prevalence and identify risk factors of congenital anomalies among neonates in Africa.

METHODS

The pooled birth prevalence of congenital anomalies was the first outcome of this review, and the pooled measure of association between congenital anomalies and related risk factors in Africa was the second. We conducted a thorough search of the databases PubMed/ Medline, PubMed Central, Hinary, Google, Cochrane Library, African Journals Online, Web of Science and Google Scholar up to 31 January 2023. The JBI appraisal checklist was used to evaluate the studies. STATA V.17 was used for the analysis. The I² test and Eggers and Beggs tests were used to measure study heterogeneity and publication bias respectively. The pooled prevalence of congenital anomalies was calculated using DerSimonian and Laird random-effect model. Subgroup analysis, sensitivity analysis and meta-regression were also performed.

RESULT

This systematic review and meta-analysis includes 32 studies with a total of 626 983 participants. The pooled prevalence of congenital anomalies was 23.5 (95% CI 20 to 26.9) per 1000 newborns. Not taking folic acid (pooled OR=2.67; 95% CI (1.42 to 5.00)), history of maternal illness (pooled OR=2.44, 95% CI (1.2 to 4.94)), history of drug use (pooled OR=2.74, 95% CI (1.29 to 5.81)), maternal age (>35 years.) (Pooled OR=1.97, 95% CI (1.15 to 3.37)), drinking alcohol (pooled OR=3.15, 95% CI (1.4 to 7.04)), kchat chewing (pooled OR=3.34, 5% CI (1.68 to 6.65)) and urban residence (pooled OR=0.58, 95% CI (0.36 to 0.95)) were had significant association with congenital anomalies.

CONCLUSION

The pooled prevalence of congenital abnormalities in Africa was found to be substantial, with significant regional variation. Appropriate folate supplementation during pregnancy, proper management of maternal sickness, proper antenatal care, referring healthcare personnel before using drugs, avoiding alcohol intake and kchat chewing are all important in lowering the occurrence of congenital abnormalities among newborns in Africa.

Natural Sympathomimetic Drugs: From Pharmacology to Toxicology

Sympathomimetic agents are a group of chemical compounds that are able to activate the sympathetic nervous system either directly via adrenergic receptors or indirectly by increasing endogenous catecholamine levels or mimicking their intracellular signaling pathways. Compounds from this group, both used therapeutically or abused, comprise endogenous catecholamines (such as adrenaline and noradrenaline), synthetic amines (e.g., isoproterenol and dobutamine), trace amines (e.g., tyramine, tryptamine, histamine and octopamine), illicit drugs (e.g., ephedrine, cathinone, and cocaine), or even caffeine and synephrine. In addition to the effects triggered by stimulation of the sympathetic system, the discovery of trace amine associated receptors (TAARs) in humans brought new insights about their sympathomimetic pharmacology and toxicology. Although synthetic sympathomimetic agents are mostly seen as toxic, natural sympathomimetic agents are considered more complacently in the terms of safety in the vision of the lay public. Here, we aim to discuss the pharmacological and mainly toxicological aspects related to sympathomimetic natural agents, in particular of trace amines, compounds derived from plants like ephedra and khat, and finally cocaine. The main purpose of this review is to give a scientific and updated view of those agents and serve as a reminder on the safety issues of natural sympathomimetic agents most used in the community.

Protein-Ligand Identification and In Vitro Inhibitory Effects of Cathine on 11 Major Human Drug Metabolizing Cytochrome P450s

Cathine is the stable form of cathinone, the major active compound found in khat (Catha edulis Forsk) plant. Khat was found to inhibit major phase I drug metabolizing cytochrome P450 (CYP) enzyme activities in vitro and in vivo. With the upsurge of khat consumption and the potential use of cathine to combat obesity, efforts should be channelled into understanding potential cathine-drug interactions, which have been rather limited. The present study aimed to assess CYPs activity and inhibition by cathine in a high-throughput in vitro fluorescence-based enzyme assay and molecular docking analysis to identify how cathine interacts within various CYPs' active sites. The half maximal inhibitory concentration (IC50) values of cathine determined for CYP2A6 and CYP3A4 were 80 and 90 μM, while CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP2J2 and CYP3A5 showed no significant inhibition. Furthermore, in Ki analysis, the Lineweaver-Burk plots depicted non-competitive mixed inhibition of cathine on both CYP2A6 and CYP3A4 with Ki value of 63 and 100 μM, respectively. Cathine showed negligible time-dependent inhibition on CYPs. Further, molecular docking studies showed that cathine was bound to CYP2A6 via hydrophobic, hydrogen and π-stacking interactions and formed hydrophobic and hydrogen bonds with active site residues in CYP3A4. Both molecular docking prediction and in vitro outcome are in agreement, granting more detailed insights for predicting CYPs metabolism besides the possible cathine-drug interactions. Cathine-drug interactions may occur with concomitant consumption of khat or cathine-containing products with medications metabolized by CYP2A6 and CYP3A4.

Clinical characteristics and treatment outcomes of patients with newly diagnosed schizophrenia: A 4-year single-center experience in Saudi Arabia

Objectives

Understanding how local “psychiatry clinic” characteristics shape research findings is essential for applying research into evolution, outcomes, and costs of mental health. However, a paucity of “psychiatry clinics” details has implications for the interpretation and utilization of this research.

Methods

We reviewed data of 746 patients with new‐onset schizophrenia on antipsychotic monotherapy seen over four years in an “adult psychiatry clinic” at Jazan Health, Saudi Arabia. Protocol‐driven interviews and investigations were recorded prospectively and extracted from the medical records for the study. Summary statistics and logistic regression analyses were applied to assess patients' characteristics and outcomes.

Results

The median patient age was 32 (IQR 27‐39) years. Of patients, 589 (79.0%) were male, and 679 (91.0%) had a low‐level education. The median follow‐up duration was 51.4 (IQR 27.4‐96.3) weeks. The most used initial antipsychotic drugs were olanzapine (48.8%), haloperidol (13.9%), and aripiprazole (11.3%). The numbers of patients who retained the initial drug at 24 and 52 weeks were 539 (72.3%) and 325 (43.6%), respectively. The initial drug was changed in 246 (33.0%) patients. The median time to initial drug change was 43.9 (IQR 14.8‐85.0) weeks. The logistic regression demonstrated that male sex (P < 0.004), young adult age group (P < 0.027), predominant positive symptoms (P < 0.021), treatment with haloperidol (P < 0.024), and khat use (P < 0.006) were significant factors for drug change.

Conclusions

This clinical records study demonstrated substantial individual variations in characteristics and in responding to initial antipsychotic medication. Insight into these findings will facilitate the planning for comprehensive research programs.

Abuse Potential of Cathinones in Humans: A Systematic Review

Introduction and objective: Assessing the abuse potential of new substances with central nervous system activity is essential for preventing possible risks of misuse and addiction. The same methodology is recommended for the evaluation of the abuse potential of recreational drugs. This systematic review aims to assess the pharmacological effects related to the abuse potential and pharmacokinetics of cathinones, which are evaluated in both experimental and prospective observational studies in humans. Materials and Methods: A systematic search of the published literature was conducted to retrieve studies that had administered cathinone, mephedrone, methylone, and diethylpropion to evaluate their acute pharmacological effects related to abuse potential. Results: The search yielded 583 results, 18 of which were included to assess the abuse potential of cathinone (n = 5), mephedrone (n = 7), methylone (n = 1), and diethylpropion (n = 5). All four substances induce stimulant and euphorigenic effects that resemble those of amphetamines and MDMA, and their different intensities may be associated with varying levels of abuse potential. Conclusions: Cathinone, mephedrone, methylone, and diethylpropion induce a range of desirable and reinforcing effects that may, to some extent, result in abuse potential. Further investigation is needed to minimize and prevent their impact on society and public health.

Khat, a Cultural Chewing Drug: A Toxicokinetic and Toxicodynamic Summary

Khat (Catha edulis) is a recreational, chewed herbal drug that has been used as a psychostimulant for centuries in East Africa and the Arabian Peninsula, namely in Somalia, Ethiopia, and Yemen. However, the growing worldwide availability of khat has produced widespread concern. The plant comprises a large number of active substances, among which cathinone, cathine, and norephedrine are the main constituents, which can be included in the group of sympathomimetics of natural origin. In fact, these compounds are amphetamine analogues, and, as such, they have amphetamine-like nervous system stimulant effects. Chewing the leaves gives people a sensation of well-being and increases energy, alertness, and self-confidence. The chronic use of khat is, however, associated with severe cardiac, neurological, psychological, and gastrointestinal complications. The psychological dependence and withdrawal symptoms of khat are the reasons for its prolonged use. The aim of this paper is to review current knowledge on the khat plant with toxicokinetic and toxicodynamic perspectives. Namely, this review paper addresses in vitro, in vivo, and human studies. The models used, as well as the concentrations and doses with the respective biological effects, are discussed. Additionally, the main drug interactions involved with khat are described.

Study of influence of Catha edulis (Khat) chewing on oral pharmacokinetics of Irbesartan in rats using a newly developed HPLC-UV method

Khat consumers might use a number of drugs for underlying conditions; however the potential drug-herb interaction between khat and other drugs including Irbesartan (IRB) is unknown. The present study was conducted to evaluate the effects of khat chewing on pharmacokinetic profile of IRB, a commonly available antihypertensive agent. The pharmacokinetic profile of orally administered IRB (15.5 mg/kg) with and without pre-administration of khat (12.4 mg/kg) were determined in Sprague-Dawley rats. IRB was estimated in rat plasma samples using a newly developed HPLC method. The chromatographic separation of the drug and internal standard (IS) was performed on a C-18 column (Raptor C-18, 100 mm × 4.6 mm id.; 5 µm) using a mobile phase consisting of 10 mM ammonium acetate buffer (pH 4.0) and acetonitrile in a ratio 60:40 v/v. Acceptable linearity for IRB was recorded at 1 – 12 µg/mL concentration range (R² > 0.99). Intra-day and inter-day precision (%RSD = 0.44% − 3.27% and 0.39–1.98% respectively) and accuracy (% recovery = 98.3 – 104.3%) in rat plasma was within the acceptable limit according to USFDA guidelines. The AUC_0-t was found to be significantly increased in IRB-khat co-administered rats as compared to rats receiving IRB only; whereas, the T_max (0.5 h) value remained unchanged. Results of this study revealed that the IRB level considerably increased in rat plasma upon co-administration of khat. This might be due to the inhibition of CYP2D9 by khat which is the principal cytochrome P450 isoform responsible for IRB metabolism.

3,4-Methylenedioxy methamphetamine, synthetic cathinones and psychedelics: From recreational to novel psychotherapeutic drugs

The utility of classical drugs used to treat psychiatric disorders (e.g., antidepressants, anxiolytics) is often limited by issues of lack of efficacy, delayed onset of action or side effects. Psychoactive substances have a long history of being used as tools to alter consciousness and as a gateway to approach the unknown and the divinities. These substances were initially obtained from plants and animals and more recently by chemical synthesis, and its consumption evolved toward a more recreational use, leading to drug abuse-related disorders, trafficking, and subsequent banning by the authorities. However, these substances, by modulation of certain neurochemical pathways, have been proven to have a beneficial effect on some psychiatric disorders. This evidence obtained under medically controlled conditions and often associated with psychotherapy, makes these substances an alternative to conventional medicines, to which in many cases the patient does not respond properly. Such disorders include post-traumatic stress disease and treatment-resistant depression, for which classical drugs such as MDMA, ketamine, psilocybin and LSD, among others, have already been clinically tested, reporting successful outcomes. The irruption of new psychoactive substances (NPS), especially during the last decade and despite their recreational and illicit uses, has enlarged the library of substances with potential utility on these disorders. In fact, many of them were synthetized with therapeutic purposes and were withdrawn for concrete reasons (e.g., adverse effects, improper pharmacological profile). In this review we focus on the basis, existing evidence and possible use of synthetic cathinones and psychedelics (specially tryptamines) for the treatment of mental illnesses and the properties that should be found in NPS to obtain new therapeutic compounds.

Khat Chewing and Lipid Profile in Human and Experimental Animals

BACKGROUND

Catha edulis, also known as khat or qat, is a plant that grows in East Africa and southern Arabia. Several millions of people chew the leaves and twigs of khat plant for their central stimulating amphetamine-like effects. Khat chewing is becoming more common in Europe and the United States, owing to worldwide migration.

OBJECTIVE

This review examines the khat ingredients, global prevalence, and legal status as well as its effects on lipid profile. Methodology. A literature search was performed using PubMed, Scopus, and Google Scholar to collect information within articles published up to April 2021 with the goal of identifying relevant studies. The proposed mechanisms of cathinone effects on total cholesterol and triglyceride were also discussed.

CONCLUSION

The khat chewing habit is considered as a serious economic and health issue that needs specialized programs to assist those people to quit or reducing this habit.

The impact of catha edulis (vahl) forssk. ex endl. (celestraceae) (khat) on pharmacokinetics of clinically used drugs

INTRODUCTION

Catha edulis (Vahl) Forssk. ex Endl. (Celestraceae) is used as a recreational drug on daily basis for its euphoric and psychostimulant effects. It is also chewed by individuals who are on medications, raising the possibility of drug-khat interaction. However, limited data are available in the literature, although clinically significant interactions are expected, as khat contains a complex mixture of pharmacologically active constituents.

AREAS COVERED

It provides an overview of the phytochemistry, pharmacokinetics, pharmacodynamics, and pharmacogenetics of khat based on the literature mined from PubMed, Google Scholar, and Cochrane databases. It also presents a detailed account of drug-khat interactions with specific examples and their clinical significance. The interactions mainly occur at the pharmacokinetics level and particular attention is paid for the phases of absorption and cytochrome P450 enzyme-mediated metabolism.

EXPERT OPINION

Despite the increasing trend of khat chewing with medications among the populace and the potential risk for the occurrence of clinically significant interactions, there is paucity of data in the literature demonstrating the magnitude of the risk. The available data, however, clearly demonstrate that the consequence of drug-khat interaction is dependent on genotype. Genotyping, where feasible, could be used to improve clinical outcome and minimize adverse reactions.

A Comparison of p53 Isoform Profiles and Apoptosis Induced by Camptothecin or a Herbal Khat Extract (Catha Edulis (Vahl) Forssk. ex Endl.) in Leukemic Cell Lines: Exploring Cellular Responses in Therapy Development

Simple Summary

This study aimed at exploring the modulations of p53 in cell toxicity induced by an extract of the herb khat, a natural stimulant used by millions of people. We previously reported that khat-extract induced cell death by affecting mitochondrial function and the receptor- and mitochondria-mediated cell death pathways, in leukemic cell lines and cells of the oral cavity, in vitro. We included the cancer therapeutic camptothecin, which induces apoptosis in various cancer cell lines. By studying modulations of p53 full-length protein and p53 β/γ isoforms following exposure to khat-extract and camptothecin, we wished to elucidate differences and similarities resulting from the treatments using MOLM-13 and MV-4-11 leukemic cell lines. Our results demonstrate that molecular effects of the cytotoxic treatments resulted in different p53 isoforms patterns and post-translational modifications. We suggest that analysis of p53 modulations could be useful in the search for new chemical probes and experimental cancer therapeutics.

Abstract

Khat (Catha edulis (Vahl) Forssk. ex Endl.) is habitually used as a natural stimulant by millions of people, but is associated with adverse effects on gastrointestinal, cardiovascular and central neural systems. At the cellular level khat toxicity involves p53 induction and cell cycle arrest, decreased mitochondrial function and activation of receptor- and mitochondria-mediated cell death pathways. In this study we have examined an extract of khat for induction of p53 post-translational modifications (PTMs) and the functional role of p53 in khat-mediated cell death. Khat was shown to induce phosphorylation and acetylation of p53 in both the khat-sensitive MOLM-13 and the khat-resistant MV-4-11 cell line, but accumulation of the full-length p53 isoform was only observed in the khat sensitive cell line. Small molecule inhibitors of p38 MAP kinase sensitized MV-4-11 cells for khat-treatment without concomitant stabilization of p53. Experiments using a p53 knock-down cell line and murine p53 knock-out bone marrow cells indicated that p53 was redundant in khat-mediated cell death in vitro. We suggest that analysis of isoform patterns and p53 PTMs are useful for elucidation of biological effects of complex plant extracts, and that p53 protein analysis is particularly useful in the search for new chemical probes and experimental cancer therapeutics.

Recent bionalytical methods for the determination of new psychoactive substances in biological specimens

One of the problems associated with the consumption of new psychoactive substances is that in most scenarios of acute toxicity the possibility of quick clinical action may be impaired because many screening methods are not responsive to them, and laboratories are not able to keep pace with the appearance of new substances. For these reasons, developing and validating new analytical methods is mandatory in order to efficiently face those problems, allowing laboratories to be one step ahead. The goal of this work is to perform a critical review regarding bionalytical methods that can be used for the determination of new psychoactive substances (phenylethylamines, cathinones, synthetic cannabinoids, opioids, benzodiazepines, etc), particularly concerning sample preparation techniques and associated analytical methods.

Exploring the Molecular Mechanisms of 17β-HSD5-induced Carcinogenicity of Catha edulis via Molecular Modeling Approach

BACKGROUND

The tradition of khat chewing has been deep-rooted in the African and Arabian Peninsula for centuries. Due to its amphetamine-like psycho-stimulant or euphoric effect, khat has been used by millions in Somalia, Ethiopia, Saudi Arabia and Yemen. The long-term use of khat can induce many major health outcomes, which may be serious and irreversible.

OBJECTIVE

Prolonged use of khat constituents has been associated with different types of cancers such as prostatic, breast and ovarian cancer. However, it has been very difficult to identify the molecular targets involved in khat carcinogenesis that interact with the Khat constituents by in vitro/in vivo experimental tools.

METHODS

In silico tools were used to predict potential targets involved in the carcinogenesis of khat. Pass on-line prediction server was used for the prediction of a potential molecular target for khat constituents. Molecular Dynamics simulation and MM-GBSA calculation of the predicted target were carried out.

RESULTS

Molecular Dynamics simulation and MM-GBSA calculation revealed that among khat constituents, β-sitosterol showed a high binding affinity towards 17β-HSD5. On the other hand, this study highlights for the first time some new interactions, which were observed in the case of cathine, cathinone and nerol during the simulation.

CONCLUSION

In silico molecular dynamic simulation tools were used for the first time to investigate the molecular mechanism of widely used leaves of psychoactive khat (Catha edulis) constituent. The present study provides deep insight to understand the effect of khat constituents involved in the impairment of the reproductive system and its binding to 17β-HSD5. ADMET profiling also suggested that few khat constituents do not fulfill the requirements of the Lipinski rule of five i.e. poor absorption and blood-brain barrier impermeability.

Coenzyme Q10 nullified khat-induced hepatotoxicity, nephrotoxicity and inflammation in a mouse model

Ethnopharmacological relevance

The consumption of khat (Catha Edulis, Forsk) is on the rise despite the much publicized associated deleterious health effects. How chemicals present in khat, affect various physiological and biochemical processes requires further scrutiny. A clear understanding of these processes will provide an avenue for countering khat-driven negative effects using appropriate pharmacological and/or nutritional interventions.

Aim of the study

The current study investigated the effect of khat on vital physiological and biochemical processes such as oxidative stress, inflammation and immune responses and the role of Coenzyme-Q₁₀ (CoQ₁₀), a potent antioxidant and anti-inflammatory, in modulating any negative effects due to khat exposure.

Methodology

Three (3) weeks old forty (40) Swiss albino mice were randomly assigned into four treatment groups (n = 10). The first group was the control that was not administered with khat or CoQ₁₀. The second group received 200 mg/kg body weight (b/w) of CoQ₁₀, while the third group received 1500 mg/kg b/w of khat extract and finally the forth group was co-treated with 200 mg/kg b/w of CoQ₁₀ and 1500 mg/kg b/w of khat extract. The experiment was conducted for 90 days after which samples were collected for physiological and biochemical analyses.

Results

The effects of khat and CoQ₁₀ on the weights of brain, liver, kidney and spleen was determined. Administration of khat decreased the levels of RBCs and its subtypes (MCV, MCH, RDW-SD and RDW-CV), a clear indicator of khat-induced normochromic microcytic anemia. White blood cells (lymphocytes, monocytes, neutrophils and eosinophil) which are vital in responding to infections were markedly elevated by khat. Moreover, these results provide evidence for khat-induced liver and kidney injury as shown by increased biomarkers; AST, ALT, GGT and creatinine respectively. Standard histopathological analysis confirmed this finding for khat-driven liver and kidney injury. Further studies showed evidence for khat-induced inflammation and oxidative stress as depicted by increased levels of the pro-inflammatory cytokine TNF-alpha and elevation of GSH in the brain, liver and spleen. Remarkably, this is the first study to demonstrate the potential of CoQ₁₀ in ameliorating khat-induced negative effects as outlined. CoQ₁₀ supplementation restored the khat-induced reduction in RBC subtypes, and was protective against liver and kidney injury as shown by the appropriate biomarkers and standard histopathology analysis. The other significant finding was the CoQ₁₀-driven normalization of GSH and TNF-α levels, indicating a protective effect from khat-driven oxidative stress and inflammation respectively.

Conclusion

From this study, we conclude that CoQ₁₀ may be useful in nullifying khat-driven deleterious events among chronic khat users.

Association between qat chewing and dyslipidaemia among young males

Objectives

This study investigated the association between qat chewing and prevalence and patterns of dyslipidaemia among young Yemeni males.

Methods

In this cross-sectional study, we used a multistage random cluster sampling method. Data were obtained using a questionnaire. Additionally, anthropometric measurements and fasting blood samples were collected. We used Program-Adult Treatment Panel III. The blood samples were analysed for lipid profile measurements including levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C).

Results

A total of 440 Yemeni male with mean age of 21.4 ± 3.6 years were enrolled. The students were divided into the following two groups—qat chewers (n = 283) and non-qat chewers (n = 77). The overall occurrence of dyslipidaemia was significantly higher in qat chewers than that in non-qat chewers (89.8% versus 80.5%) (P < 0.05). Hypercholesterolaemia, hypertriglyceridaemia, high LDL-C level, and mixed hyperlipidaemia were lower in qat chewers than in non-qat chewers (16.6%, 58.3%, 16.3%, and 10.6%, respectively, versus 20.8%, 64.9%, 18.2%, and 20.8%, respectively). Isolated hypertriglyceridaemia was slightly higher in qat chewers than in non-qat chewers (47.7% versus 44.2%). However, the incidence of low HDL-C level, isolated low HDL-C level, and isolated hypercholesterolaemia were generally higher in qat chewers than in non-qat chewers (83%, 25.1%, and 6%, respectively, versus 75.3%, 15.6%, and 0%, respectively).

Conclusion

This study showed high prevalence of dyslipidaemia among Yemeni male qat chewers. Low HDL-C level was the main lipid variable, followed by hypertriglyceridaemia. Genetic factors, war conditions, physical inactivity, and low-fat traditional Yemeni diet were considered the determinants of the study findings.

Involvement of CB2 Receptors in the Neurobehavioral Effects of Catha Edulis (Vahl) Endl. (Khat) in Mice

There is behavioral evidence for the interaction between crude khat extract and the endocannabinoid system, whereby the endocannabinoid system alters khat extract-mediated behavioral effects through modulation of the monoaminergic system. The objective of this study was to investigate the role of the endocannabinoid system on the neurobehavioral effect of khat extract in mice following concomitant administration of khat extract and the CB2R agonist, JWH133. Locomotor activity test, immunohistochemistry, and reverse transcriptase polymerase chain reaction technique were utilized to assess locomotor activity, tyrosine hydroxylase immunoreactivity, and expression of dopamine transporter mRNA gene. The results show sub-acute administration of khat extract alone increased locomotor activity in mice and co-administration of the CB2R agonist, JWH133, reduced khat extract induced hyperlocomotor activity. The data revealed that cell type specific deletion of CB2Rs on dopaminergic neurons increased the hyperlocomotor behavior of khat extract. Furthermore, the results revealed that khat extract attenuated MPTP induced motor deficits, which is enhanced by JWH133. Khat extract also increased expression of tyrosine hydroxylase positive cells and expression of dopamine transporter mRNA gene in wild type mice. Nevertheless, JWH133 did not alter the effect of khat extract on tyrosine hydroxylase immunoreactivity and dopamine transporter mRNA expression when given together with khat extract. Taken together, the results suggest that the CB2Rs selectively interact with khat extract-mediated locomotor effects and could be utilized as therapeutic target in central nervous system movement disorders associated with dopamine dysregulation.

Prevalence of dyslipidemia among students of a Yemeni University

Objectives

To estimate the prevalence of dyslipidemia and patterns of lipid profile and associated factors among Yemeni university students.

Methods

This cross-sectional study included 240 Yemeni students (116 males and 124 females) at Ibb University. The students were randomly selected from various faculties of the university. Demographic and clinical data were obtained from all participants. Fasting blood specimens were collected from all students for measurement of serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). The criteria of the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) were used.

Results

The mean age of the studied cohort was 19.8 ± 1.8 years; 48.3% were men and 51.7% were women. About 56.7% of the participants were from rural areas. Qat chewers and cigarette smokers comprised 63.3% and 6.7% of the cohort, respectively. No obese students were found in this study; however, 11.7% were overweight. The overall prevalence of dyslipidemia, hypercholesterolemia, hypertriglyceridemia, high LDL-C, and low HDL-C among the participating students were 86.7%, 21.7%, 23.8%, 31.7%, and 81.7%, respectively. Mixed hyperlipidemia was present in 8.8% of the students. The prevalence of isolated hypercholesterolemia, hypertriglyceridemia, and low HDL-C was 12.9%, 15%, and 70%, respectively. Dyslipidemia was significantly associated with male sex, increasing age, urban residence, and medical and natural science faculties. In contrast, smoking, qat chewing, physical activity, and the consumption of fast food, fruits and vegetables, and fish were not significantly associated with dyslipidemia.

Conclusion

To our knowledge, this is the first human study conducted at Ibb University during wartime in Yemen. Dyslipidemia was highly prevalent among healthy Yemeni university students in Ibb city. Low HDL-C was the most prevalent type of dyslipidemia, followed by increased levels of LDL-C. Gender, age, residence, and type of faculty were also closely related to dyslipidemia. These results indicate the need for specialized programs to determine blood lipid levels and initiate intervention programs to reduce the prevalence and prevent the complications of dyslipidemia among Yemeni university students.

Acute Liver Injury Associated with Khat Use in a 24-Year-Old Male

Chewing khat leaves (Catha edulis) is common cultural practice in Eastern African countries. Khat has been implicated in cases of acute liver injury, sometimes leading to liver failure and requiring transplantation. We report the case of a 24-year-old gentleman presenting with symptoms of acute liver failure. Bloodwork demonstrated hepatocyte-predominant liver injury. Microbiological and serological hepatitis panels were negative, and his liver biopsy demonstrated acute cholestatic hepatitis. He admitted to regular khat use for several years prior to his presentation. His liver function tests improved with cessation of khat use. This is the first reported case of acute khat-associated hepatitis in Canada. Considering cultural practices such as khat chewing in presentations of acute liver injury are important when caring for diverse patient populations.

Effects of Khat (Catha edulis) use on catalytic activities of major drug-metabolizing cytochrome P450 enzymes and implication of pharmacogenetic variations

In a one-way cross-over study, we investigated the effect of Khat, a natural amphetamine-like psychostimulant plant, on catalytic activities of five major drug-metabolizing cytochrome P450 (CYP) enzymes. After a one-week Khat abstinence, 63 Ethiopian male volunteers were phenotyped using cocktail probe drugs (caffeine, losartan, dextromethorphan, omeprazole). Phenotyping was repeated after a one-week daily use of 400 g fresh Khat leaves. Genotyping for CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A5 were done. Urinary cathinone and phenylpropanolamine, and plasma probe drugs and metabolites concentrations were quantified using LC-MS/MS. Effect of Khat on enzyme activities was evaluated by comparing caffeine/paraxanthine (CYP1A2), losartan/losartan carboxylic acid (CYP2C9), omeprazole/5-hydroxyomeprazole (CYP2C19), dextromethorphan/dextrorphan (CYP2D6) and dextromethorphan/3-methoxymorphinan (CYP3A4) metabolic ratios (MR) before and after Khat use. Wilcoxon-matched-pair-test indicated a significant increase in median CYP2D6 MR (41%, p < 0.0001), and a marginal increase in CYP3A4 and CYP2C19 MR by Khat. Repeated measure ANOVA indicated the impact of CYP1A2 and CYP2C19 genotype on Khat-CYP enzyme interactions. The median MR increased by 35% in CYP1A2*1/*1 (p = 0.07) and by 40% in carriers of defective CYP2C19 alleles (p = 0.03). Urinary log cathinone/phenylpropanolamine ratios significantly correlated with CYP2D6 genotype (p = 0.004) and CYP2D6 MR (P = 0.025). Khat significantly inhibits CYP2D6, marginally inhibits CYP3A4, and genotype-dependently inhibit CYP2C19 and CYP1A2 enzyme activities.

Antioxidant capacity and biomarkers of oxidative stress in saliva of khat-chewing patients: a case-control study

OBJECTIVES

The aim of this study was to investigate the antioxidant levels and biomarkers of oxidative stress in saliva from khat-chewing patients compared with controls.

STUDY DESIGN

Saliva samples were collected from 51 chronic khat chewers and 46 age- and sex-matched controls. Concentrations of oxidative stress biomarkers (malonyl-dialdehyde [MDA], protein carbonyl, and 8-hydroxy-2'-deoxyguanosine) and antioxidant defense (total antioxidant capacity [TAC], superoxide dismutase, glutathione peroxidase, and catalase [CAT) were analyzed.

RESULTS

Salivary MDA level in the khat users group (45 ± 9.2 nmol/mL) was significantly increased in comparison with controls (13 ± 2.1 nmol/mL; P < .001), but there were no significant differences between the 2 groups regarding the levels of salivary protein carbonyl and oxidized guanine species. Salivary TAC was significantly reduced in khat users (0.25 ± 0.028 mmol/L) in comparison with controls (0.34 ± 0.037 mmol/L). Salivary CAT level was significantly reduced in khat users (6.0 ± 0.47 U/mL) in comparison with controls (7.7 ± 0.43 units/mL; P <.05), but no significant differences were observed between the 2 groups with regard to salivary superoxide dismutase or glutathione peroxidase levels.

CONCLUSIONS

Chronic khat chewing is associated with increased levels of salivary MDA and reduced levels of TAC and CAT among a population of adult men in comparison with non-khat-chewing controls. These findings suggest that the pro-oxidative effect of khat chewing may be a contributing mechanism for various oral diseases associated with khat use, including cancer, periodontitis, and caries.

Neuropharmacology of Synthetic Cathinones

Synthetic cathinones are derivatives of the naturally occurring compound cathinone, the main psychoactive ingredient in the khat plant Catha edulis. Cathinone is the β-keto analog of amphetamine, and all synthetic cathinones display a β-keto moiety in their structure. Several synthetic cathinones are widely prescribed medications (e.g., bupropion, Wellbutrin^®), while others are problematic drugs of abuse (e.g., 4-methylmethcathinone, mephedrone). Similar to amphetamines, synthetic cathinones are psychomotor stimulants that exert their effects by impairing the normal function of plasma membrane transporters for dopamine (DAT), norepinephrine (NET), and 5-HT (SERT). Ring-substituted cathinones like mephedrone are transporter substrates that evoke neurotransmitter release by reversing the normal direction of transporter flux (i.e., releasers), whereas pyrrolidine-containing cathinones like 3,4-methylenedioxypyrovalerone (MDPV) are potent transporter inhibitors that block neurotransmitter uptake (i.e., blockers). Regardless of molecular mechanism, all synthetic cathinones increase extracellular monoamine concentrations in the brain, thereby enhancing cell-to-cell monoamine signaling. Here, we briefly review the mechanisms of action, structure-activity relationships, and in vivo pharmacology of synthetic cathinones. Overall, the findings show that certain synthetic cathinones are powerful drugs of abuse that could pose significant risk to users.