The Effect Of Mitragynine On Cyclic Amp Formation And Mrna Expression Of Mu-Opioid Receptors Mediated By Chronic Morphine Treatment In Sk-N-Sh Neuroblastoma Cell

Mitragynine is an indole alkaloid compound of Mitragyna speciosa (M.speciosa) Korth. (Rubiaceae). In Thailand, this plant is known as “Kratom” and in Malaysia it is known as “Biak-biak” or “Ketum”. M. speciosa was used as substitution therapy for chronic opioid treatment to manage the withdrawal symptoms in Malaysia and Thailand. To date over 40 compounds have been isolated from the leaves of this plant. Mitragynine is the most abundant of the more than 25 alkaloids of Kratom (66% of the crude base) and is responsible for the substance’s opioid effects. The bioactive compound mitragynine from M.speciosa was isolated using acid-base extraction followed by a column chromatography method. In this study, we had investigated the cellular mechanism of chronic morphine treatment after co- and pre-treatment with mitragynine in production of forskolin stimulation cyclic adenosine monophosphate (cAMP) and expression of mu-opioid receptor (MOR) during the differentiation of SK-N-SH human neuroblastoma cells, the possible mechanisms involved in those changes, and the differential effects of morphine and mitragynine. cAMP is a molecule that is controlled by G protein-coupled receptor activation and other cellular processes. Measurement of cAMP levels in cell is widely used as an indicator of receptors function in drug discovery application

In vivo toxicity study of Erythroxylum cuneatum leaves extract and its effects on working memory of rats

Erythroxylum cuneatum has been traditionally proven to possess beneficial properties in treating drug addiction and other illness. Due to less information on this plant, this elusive plant was investigated further to evaluate the in vivo toxicity profile of the plant and to investigate the effect of E. cuneatum on cognitive performance in rats. Two different extracts were produced from the leaves of E. cuneatum which were aqueous and alkaloid extracts. Acute in vivo toxicity test was evaluated in ICR mice to determine their medium lethal dose 50 value. In the in-vivo toxicity study, aqueous extract showed the almost similar toxic effect as alkaloid extract which was 416.86 mg/kg for alkaloid extract and 316.23 mg/kg for aqueous extract. These findings suggesting that aqueous and alkaloid extracts showed toxic effects at the high dose, thus safe at a low dose. Working memory task using novel object discrimination test (NOD) was performed for the determination of neurobehavioral profiles. In the NOD test, alkaloid-treated rats did not show any significant discrimination between the familiar and novel object (P > 0.05); thus it can be interpreted as not induce a memory defi cit. It can also be postulated that the extract has no effect on memory and learning neither improvises nor impairs the cognitive function. In conclusion, since E. cuneatum does not show any impairment on cognitive, its pharmacological properties could be further investigated without significant changes in cognitive performance

Mitragynine Attenuates Withdrawal Syndrome in Morphine-Withdrawn Zebrafish

A major obstacle in treating drug addiction is the severity of opiate withdrawal syndrome, which can lead to unwanted relapse. Mitragynine is the major alkaloid compound found in leaves of Mitragyna speciosa, a plant widely used by opiate addicts to mitigate the harshness of drug withdrawal. A series of experiments was conducted to investigate the effect of mitragynine on anxiety behavior, cortisol level and expression of stress pathway related genes in zebrafish undergoing morphine withdrawal phase. Adult zebrafish were subjected to two weeks chronic morphine exposure at 1.5 mg/L, followed by withdrawal for 24 hours prior to tests. Using the novel tank diving tests, we first showed that morphine-withdrawn zebrafish display anxiety-related swimming behaviors such as decreased exploratory behavior and increased erratic movement. Morphine withdrawal also elevated whole-body cortisol levels, which confirms the phenotypic stress-like behaviors. Exposing morphine-withdrawn fish to mitragynine however attenuates majority of the stress-related swimming behaviors and concomitantly lower whole-body cortisol level. Using real-time PCR gene expression analysis, we also showed that mitragynine reduces the mRNA expression of corticotropin releasing factor receptors and prodynorphin in zebrafish brain during morphine withdrawal phase, revealing for the first time a possible link between mitragynine's ability to attenuate anxiety during opiate withdrawal with the stress-related corticotropin pathway

Clinicians’ Perceived Understanding of Biostatistical Results in the Medical Literature: A Cross-Sectional Study

Background and objectives: The continuum of evidence-based medicine (EBM) depends solely on clinicians’ commitment to keep current with the latest clinical information. Exploration on clinicians’ understanding of biostatistical results in the medical literature is sparse to date. This study aimed to evaluate clinicians’ perceived understanding of biostatistical results in the medical literature and the factors influencing them. Materials and Methods: A cross-sectional study was conducted among 201 clinicians at the Seberang Jaya Hospital, a cluster-lead research hospital in Northern Malaysia. A self-administered questionnaire that consisted of items on sociodemographics, validated items on clinicians’ confidence level in interpreting statistical concepts, perceived understanding of biostatistics, and familiarity with different statistical methods were used. Descriptive, univariate, and multivariate analyses were conducted. Results: Perceived understanding of biostatistical results among clinicians in our sample was nearly 75%. In the final regression model, perceived understanding was significantly higher among clinicians who were able to interpret p-values with complete confidence (AOR = 3.0, 95% CI 1.1−8.1), clinicians who regularly encounter measures of central tendencies (AOR = 2.3, 95% CI 1.1−5.2), and clinicians who regularly encounter inferential statistics (AOR = 2.2, 95% CI 1.1−4.5) while appraising the medical literature. Conclusions: High perceived understanding was significantly associated with clinicians’ confidence in interpreting statistical concepts and familiarity with different statistical methods. Our findings form a platform to understand clinicians’ ability to appraise rigorous biostatistical results in the medical literature for the retrieval of evidence-based data to be used in routine clinical practice

Influence of Population Density for COVID-19 Spread in Malaysia: An Ecological Study

The rapid transmission of highly contagious infectious diseases within communities can yield potential hotspots or clusters across geographies. For COVID-19, the impact of population density on transmission models demonstrates mixed findings. This study aims to determine the correlations between population density, clusters, and COVID-19 incidence across districts and regions in Malaysia. This countrywide ecological study was conducted between 22 January 2021 and 4 February 2021 involving 51,476 active COVID-19 cases during Malaysia’s third wave of the pandemic, prior to the reimplementation of lockdowns. Population data from multiple sources was aggregated and spatial analytics were performed to visualize distributional choropleths of COVID-19 cases in relation to population density. Hierarchical cluster analysis was used to synthesize dendrograms to demarcate potential clusters against population density. Region-wise correlations and simple linear regression models were deduced to observe the strength of the correlations and the propagation effects of COVID-19 infections relative to population density. Distributional heats in choropleths and cluster analysis showed that districts with a high number of inhabitants and a high population density had a greater number of cases in proportion to the population in that area. The Central region had the strongest correlation between COVID-19 cases and population density (r = 0.912; 95% CI 0.911, 0.913; p < 0.001). The propagation effect and the spread of disease was greater in urbanized districts or cities. Population density is an important factor for the spread of COVID-19 in Malaysia

Spatial Dynamics and Multiscale Regression Modelling of Population Level Indicators for COVID-19 Spread in Malaysia

As COVID-19 dispersion occurs at different levels of gradients across geographies, the application of spatiotemporal science via computational methods can provide valuable insights to direct available resources and targeted interventions for transmission control. This ecological-correlation study evaluates the spatial dispersion of COVID-19 and its temporal relationships with crucial demographic and socioeconomic determinants in Malaysia, utilizing secondary data sources from public domains. By aggregating 51,476 real-time active COVID-19 case-data between 22 January 2021 and 4 February 2021 to district-level administrative units, the incidence, global and local Moran indexes were calculated. Spatial autoregressive models (SAR) complemented with geographical weighted regression (GWR) analyses were executed to determine potential demographic and socioeconomic indicators for COVID-19 spread in Malaysia. Highest active case counts were based in the Central, Southern and parts of East Malaysia regions of Malaysia. Countrywide global Moran index was 0.431 (p = 0.001), indicated a positive spatial autocorrelation of high standards within districts. The local Moran index identified spatial clusters of the main high–high patterns in the Central and Southern regions, and the main low–low clusters in the East Coast and East Malaysia regions. The GWR model, the best fit model, affirmed that COVID-19 spread in Malaysia was likely to be caused by population density (β coefficient weights = 0.269), followed by average household income per capita (β coefficient weights = 0.254) and GINI coefficient (β coefficient weights = 0.207). The current study concluded that the spread of COVID-19 was concentrated mostly in the Central and Southern regions of Malaysia. Population’s average household income per capita, GINI coefficient and population density were important indicators likely to cause the spread amongst communities

Effect of two weeks chronic morphine treatment (1.5 mg/L), 24-h morphine withdrawal and morphine withdrawal in presence of mitragynine (1 mg/L or 2 mg/L) on whole-body cortisol (µg/g fish).

<p>Data are presented as mean ± SEM. (Control, n = 16; morphine treatments, n = 14; morphine withdrawal, n = 21; 1.0 mg/L Mitragynine, n = 23; 2 mg/L Mitragynine, n = 20). Mean values were subjected to one way ANOVA and where applicable, ranked by Tukey test (P<0.05); values with same letter are not significantly different.</p

Effect of two weeks chronic morphine treatment (1.5 mg/L), 24-h morphine withdrawal and morphine withdrawal in presence of 2 mg/L mitragynine on the mRNA expression of CRF-R1, CRF-R2 and PDYN in zebrafish.

<p>Data are presented as mean ± SEM of three independent experiments. Mean values were subjected to one way ANOVA and where applicable, ranked by Tukey test (P<0.05); mean percentage values with same letter are not significantly different.</p

Primer sequences used for semi-quantitative real time PCR gene expression study of corticotropin-releasing factor type 1 receptor, corticotropin-releasing factor type 2 receptor and prodynorphin.

<p>Each sequence is listed starting from the 5′-end and its corresponding sequence ID are provided. F, forward primer; R, reverse primer.</p

Effects of morphine treatment, morphine withdrawal and mitragynine on swimming behavior in adult zebrafish using the novel tank diving test.

<p>(A). Effect of two weeks chronic morphine treatment (1.5 mg/L), 24 h morphine withdrawal and morphine withdrawal in presence of 2 mg/L mitragynine on swimming behavior of zebrafish. (Control, n = 17; morphine treatments, n = 25; morphine withdrawal, n = 22; morphine withdrawal+mitragynine, n = 22). All data were presented in mean ± SEM. Mean values were subjected to one way ANOVA and where applicable, ranked by Tukey test (P<0.05); mean values with same letter are not significantly different. (B) Effect of 20 min acute mitragynine treatment (1 mg/L and 2 mg/L) on swimming behavior of zebrafish. (Control, n = 21; 1 mg/L mitragynine, n = 20; 2 mg/L mitragynine, n = 21). All data were presented in mean ± SEM. Mean values were subjected to one way ANOVA and where applicable, ranked by Tukey test (P<0.05); mean values with same letter are not significantly different.</p