Targeting Chemokines and Chemokine Receptors in Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is an immune-mediated and neurodegenerative disorder that results in inflammation and demyelination of the central nervous system (CNS). MS symptoms include walking difficulties, visual weakening, as well as learning and memory impairment, thus affecting the quality of the patient's life. Chemokines and chemokine receptors are expressed on the immune cells as well as the CNS resident cells. Several sets of chemokine receptors and their ligands tend to be pathogenic players in MS, including CCL2, CCL3, CCL4, CCL5, CCL7, CCL8, CCL11, CCL17, CCL19, CCL21, CCL22, CXCL1, CXCL8, CXCL9, CXCL10, CXCL11, and CXCL16. Furthermore, current modulatory drugs that are used in the treatment of MS and its animal model, the experimental autoimmune encephalomyelitis (EAE), affect the expression of several chemokine and chemokine receptors. In this review, we highlight the pathogenic roles of chemokines and their receptors as well as utilizing them as potential therapeutic targets through selective agents, such as specific antibodies and receptor blockers, or indirectly through MS or EAE immunomodulatory drugs.

Respiratory sinus arrhythmia and central respiratory drive in humans

1. The influence of central inspiratory drive on heart rate variability was investigated in young human subjects using power spectral analysis of R-R intervals. 2. The area of the high-frequency component occurring at the respiratory frequency (0.2-0.25 Hz) in the power spectral density curves was used as an index of respiratory sinus arrhythmia. 3. Central inspiratory drive was increased by breathing a CO2-enriched (5%) gas mixture and this condition was compared with a similar degree of ventilation produced voluntarily. 4. Tests were conducted on eight young subjects with and without low-dose scopolamine (scopoderm TTS) in a double-blind cross-over trial. 5. Scopolamine decreased heart rate and increased the high-frequency peak, suggesting that its main action on the cardiac vagal pathway was a peripheral one, possibly increasing the efficacy of vagal impulses on the cardiac pacemaker. 6. With scopolamine, CO2 breathing increased the area of the high-frequency component significantly more than a similar degree of ventilatory movements produced by voluntary hyperventilation. 7. It is concluded that respiratory sinus arrhythmia in humans is at least partly dependent on a central respiratory-cardiac coupling, most probably similar to that shown in animal studies.

Drugs for Multiple Sclerosis Activate Natural Killer Cells: Do They Protect Against COVID-19 Infection?

COVID-19 infection caused by the newly discovered coronavirus severe acute respiratory distress syndrome virus-19 (SARS-CoV-2) has become a pandemic issue across the globe. There are currently many investigations taking place to look for specific, safe and potent anti-viral agents. Upon transmission and entry into the human body, SARS-CoV-2 triggers multiple immune players to be involved in the fight against the viral infection. Amongst these immune cells are NK cells that possess robust antiviral activity, and which do not require prior sensitization. However, NK cell count and activity were found to be impaired in COVID-19 patients and hence, could become a potential therapeutic target for COVID-19. Several drugs, including glatiramer acetate (GA), vitamin D₃, dimethyl fumarate (DMF), monomethyl fumarate (MMF), natalizumab, ocrelizumab, and IFN-β, among others have been previously described to increase the biological activities of NK cells especially their cytolytic potential as reported by upregulation of CD107a, and the release of perforin and granzymes. In this review, we propose that such drugs could potentially restore NK cell activity allowing individuals to be more protective against COVID-19 infection and its complications.

Exercise and diving, two conflicting stimuli influencing cardiac vagal tone in man

1. In order to increase our understanding of the central regulation of human cardiac vagal motoneurones we studied the interaction between two opposing influences on cardiac vagal tone, one related to diving and the other to exercise. 2. The heart rate response to cooling the face (0 degrees C, trigeminal cutaneous receptor stimulation, TGS) and to a brief isometric muscle contraction was studied in fourteen healthy young adults (8 males, 6 females) during controlled ventilation at supine rest. 3. Fluctuations in R-R interval were quantified by spectral analysis. In addition the absolute values of R-R intervals occurring in any one of ten arbitrary phases of a respiratory cycle were measured over thirty to sixty cycles to give a graph of the changes in R-R interval throughout a respiratory cycle. 4. TGS produced a significant decrease in heart rate (-21 +/- 2 beats min-1 in females, -19 +/- 2 beats min-1 in males; means +/- S.E.M.). In addition the autospectral plots of R-R interval variability showed that during TGS there was a significant increase both in the high frequency peak and in the low frequency peak in all subjects. These data suggested that in these experiments the bradycardia of TGS was due to an increase in cardiac vagal tone. 5. Voluntary isometric contractions at 40 and 60% of maximum (40% MVC, 60% MVC) were timed to occur early in expiration or early in inspiration. Analysis of the changes in R-R interval produced by these contractions was confined to the respiratory cycle in which they were initiated. The early onset of these changes was interpreted as showing a decrease in cardiac vagal tone. 6. The 40% MVC and 60% MVC increased heart rate significantly within one respiratory cycle with maximum effects having a mean of 9.5 +/- 3 and 11 +/- 3 beats min-1, respectively. When isometric muscle contraction was initiated during TGS the 60% MVC but not the 40% MVC was able to significantly decrease R-R interval and hence increase heart rate. 7. It is concluded that the TGS excitatory inputs and the muscle inhibitory inputs to cardiac vagal neurones do not interact by one input gating the other early in the pathway but more probably by a process of algebraic summation closer to the cardiac vagal neurone.

Rituximab Prevents the Development of Experimental Autoimmune Encephalomyelitis (EAE): Comparison with Prophylactic, Therapeutic or Combinational Regimens

Objective

To investigate, in detail, the effects of rituximab (RTX), an off-label drug for treating multiple sclerosis (MS) disease on preventing and/or ameliorating experimental autoimmune encephalomyelitis (EAE).

Methods

Using bioinformatics analysis of publicly available transcriptomics data, we determined the accumulation of B cells, plasma cells and T cells in different compartments of multiple sclerosis patients (MS) and healthy individual brains. Based on these observations and on the literature search, we dosed RTX in EAE mice either orally, or injected intraperitoneally (IP). The latter route was used either prophylactically (asymptomatic stage; upon the induction of the disease), or therapeutically (acute stage; upon the appearance of the first sign of the disease). Further, we used RTX as a preventive drug either as a single agent or in combination with other routes of administration.

Results

Because no complete recovery was observed when RTX was used prophylactically or therapeutically, we devised another protocol of injecting this drug before the onset of the disease and designated this regiment as prevention. We demonstrated that the 20 μg/mouse prevention completely reduced the EAE clinical score, impaired infiltration of T and B cells into the perivascular space of mice brains, along with inhibiting the inflammation and demyelination. However, the 5 and 10 μg/mouse doses although reduced all aspects of inflammation in these mice, their effects were not as potent as the 20 μg/mouse RTX dose. Finally, we combined the 5 μg/mouse prevention treatment with either the prophylactic or therapeutic regimen and observed a robust effect.

Conclusion

We observed that combinatorial regimens resulted in further reduction of inflammation, T and B cell extravasation into the brains of EAE mice and improved the re-myelination.

The metabolism of salicylidene benzylamine, a pro-drug for salicylate, in rats and dogs

1. Oral doses of [14C]salicylidene benzylamine were well absorbed by rats and dogs and excreted mainly in the urine (92% dose by rat in 24 h and 84% by dog in 48 h). 2. After 50, 100 and 300 mg/kg oral doses to rats, peak mean plasma 14C concn. (mainly salicylic acid) of 77, 243 and 396 micrograms equiv./ml respectively were reached between 2 and 4 h and maintained at this level until about 7.5 h. 14C was cleared more rapidly from the plasma of male rats than from that of female rats. After 44, 85 and 300 mg/kg oral doses to dogs, peak mean plasma 14C concn. (mainly salicylic acid) of 114, 194 and 320 micrograms equiv./ml respectively were reached at 4 h and then declined with a half-life of 6-7 h. 3. Tissue 14C concn. in both species were greatest at the times of peak plasma 14C concn., but in general were lower than those in the corresponding plasma. 4. The major components in rat and dog urine were salicyl alcohol, salicylic acid and salicyluric acid, the first two being excreted partly as glucuronic acid/sulphate conjugates. After initial hydrolysis of salicylidene benzylamine to salicylaldehyde, approximately equal amounts were reduced and oxidized to the corresponding alcohol and acid respectively.

Hippuric acid excretion after benzylamine ingestion in man

The fate of 14C-benzylamine after oral administration as the hydrochloride has been investigated in two male volunteers. Over 98% of the administered radiolabel was excreted in the urine as 14C-hippuric acid within 24 hours. The rate of urinary hippuric acid excretion was extremely rapid, with more than 90% of the dose excreted after three hours.

GLC determination of purity of Schiff bases bakrine and saddamine

GLC methods were developed for the investigation of impurities in bakrine and saddamine. The method used for bakrine was unsuitable for saddamine since two possible saddamine impurities, benzylamine and salicylaldehyde, reacted very readily in solution to form saddamine, thus giving a false low value for the original concentration of these impurities. The method devised for saddamine involved silylation, which greatly reduced the possibility of saddamine formation from its precursors and also enabled the detection of another possible impurity, salicylic acid. The method described has an obvious application to the determination of other Schiff bases.

The metabolism of saddamine in man: the fate of the benzylamine moiety of saddamine

The metabolism of 14C-saddamine radiolabelled in the benzylamine moiety has been investigated in man after oral administration. 14C-Hippuric acid was found to be the only radiolabelled urinary metabolite, the overall amount of which was equivalent to over 95% of the dose. The time taken for elimination of 50% of the dose in the urine was approximately five hours and the corresponding value for 14C-benzylamine hydrochloride was less than one hour.

Empowering precision medicine: Insights from a national survey on pharmacogenomics knowledge, attitudes, and perceptions among community pharmacists in the UAE

Background

Community pharmacists are essential to pharmacogenomics implementation because they can help trainers, clinical advisors, and other medical professionals understand the importance of pharmacogenomics and encourage them to use it in their practice. This study is to evaluate the community pharmacists' understanding, attitudes, and perceptions of pharmacogenomics in the United Arab Emirates (UAE).

Methods

Professionals employed at community pharmacies in Abu Dhabi, Dubai, and the Northern Emirates participated in a cross-sectional study design. From July 2023 to February 2024, five pharmacy students in their last year conducted the survey. The study team employed a structured questionnaire to collect data in addition to conducting in-person interviews. The study questionnaire comprised three distinct sections namely, demographic information, knowledge of pharmacogenomics concepts, and perceptions regarding pharmacogenomics.

Results

A total of 586 pharmacists enrolled in the study. The average knowledge score regarding pharmacogenomics was 75.1 % with a 95 % confidence interval (CI) of [72.4 %, 77.7 %]. The average attitude score toward pharmacogenomics was 67.5 % with a 95 % CI of [66.3 %, 68.7 %]. Better pharmacogenomics knowledge among several groups: independent pharmacies (OR 1.7; 95 % CI 1.2-2.4), Pharmacists in Charge (OR 1.4; 95 % CI 1.3-2.02), pharmacists with 11-15 years of experience (OR 2.1; 95 % CI 1.4-4.2), graduates from international universities (OR 4.6; 95 % CI 1.6-12.9), and those who received training on pharmacogenomics (OR 11.9; 95 % CI 3.3-14.5). Similarly, better attitude scores were observed among independent pharmacies (OR 1.5; 95 % CI 1.1-2.1), Pharmacists in Charge (OR 1.5; 95 % CI 1.07-2.1), pharmacists with 16-20 years of experience (OR 2.1; 95 % CI 1.16-3.7), graduates regional universities (OR 1.47; 95 % CI 1.05-2.1), and those who received training on pharmacogenomics (OR 4.8; 95 % CI 3.2-7.3).

Conclusion

The positive attitudes toward pharmacogenomics that we found in our research indicate that community pharmacists in the United Arab Emirates are beginning to realize the potential advantages of pharmacogenomics in terms of improving patient care. Policies ensuring the privacy and confidentiality of genetic information are also necessary in considering concerns about the availability of genetic test results to insurance companies and potential employers.

Use of opposing reflex stimuli and heart rate variability to examine the effects of lipophilic and hydrophilic beta-blockers on human cardiac vagal control

Evidence from animal studies suggests that beta-blockers can act within the central nervous system to increase cardiac vagal motoneuron activity. We have attempted to determine whether such an effect is evident in healthy humans, by examining the effects of lipophilic and hydrophilic agents on heart rate variability and cardiac vagal reflexes. A total of 20 healthy volunteers took part in the study. Autonomic studies were performed after 72 h of treatment with placebo, atenolol or metoprolol in a blinded cross-over design. ECG recordings were taken at rest and during mental and orthostatic stress. Heart rate variability was measured in the time and frequency domains. The effects on heart rate of two opposing cardiac vagal reflexes were examined. Trigeminal stimulation causing vagal stimulation, and isometric forearm muscle contraction ('muscle heart reflex') causing vagal inhibition, were performed alone and simultaneously. At rest, during mental stress and during trigeminal stimulation, beta-blocker therapy was associated with significantly increased high-frequency beat-to-beat heart rate variability when compared with placebo. There were no significant differences in effects on heart rate or heart rate variability between atenolol and metoprolol. Analysis of the muscle heart reflex, alone and with simultaneous trigeminal stimulation, showed that the magnitude of the R-R interval response was significantly greater after beta-blocker therapy compared with placebo, but the effects of atenolol and metoprolol were equivalent. beta-Blocker therapy increased cardiac vagal activity, as shown by measures of high-frequency heart rate variability and reflex studies. Lipophilic and hydrophilic beta-blockers appeared to be equally efficacious in increasing the cardiac vagal modulation of heart rate.

Molecular Examination of Differentially Expressed Genes in the Brains of Experimental Autoimmune Encephalomyelitis Mice Post Herceptin Treatment

Objective

Herceptin (trastuzumab) is an approved drug for treating HER2⁺ breast cancer patients, but its use for other diseases is not established. We sought to investigate the effects of Herceptin on ameliorating experimental autoimmune encephalomyelitis (EAE) and to examine its effects on the expression of various genes.

Methods

We used in-silico analysis of publicly available data, qRT-PCR, and immunohistochemistry (IHC) to determine the expression of HER2⁺ cells in the brains of EAE mice. IHC was also utilized to determine the anti-inflammatory effects of Herceptin. The ability of Herceptin to alleviate the EAE clinical score was measured in these mice. Bioinformatics analysis of publicly available data and qRT-PCR were performed to investigate the differentially expressed genes that were either up-regulated or down-regulated during the high clinical score (HCS) of the disease.

Results

We observed that HER2/Erbb2, the receptor for Herceptin is upregulated in the brains of EAE mice when the brains were examined at the HCS stage. Further, we demonstrated that Herceptin ameliorates the EAE disease, increasing re-myelination, reducing brain inflammation, CD3⁺ T cell accumulation, and HER2⁺ cells in the brains of these mice. Molecular analysis demonstrated the expression of different genes that were either up-regulated or down-regulated during the HCS of the disease. Our combined bioinformatics and qRT-PCR analyses show increased mRNA expression of Atp6v0d2, C3, C3ar1, Ccl3, Ccl6, Cd74, Clec7a, Cybb, H2-Aa, Hspb1, Lilr4b, Lilrb4a, Mpeg1, Ms4a4a, Ms4a6c, Saa3, Serpina3n and Timp1, at HCS. Except for the mRNA levels of Cd74 and Clec7a which were increased at HCS when Herceptin was used in both prophylactic and therapeutic regimens, the levels of other described mRNAs were reduced.

Conclusion

These novel findings show that Herceptin ameliorates the clinical score in EAE mice and are the first to investigate in detail the differential gene expression post-treatment with the drug.

Assessing Students' Knowledge and Attitudes Regarding the Risks and Prevention of Consanguineous Marriage: A Cross-Sectional Online Survey

BACKGROUND

Several studies indicate a correlation between consanguinity and genetic disorders, congenital malformations, harm to reproductive health, and increased child mortality.

OBJECTIVE

To assess students' knowledge and attitudes about risks and prevention of consanguineous marriage.

METHODS

Demographic details of the participants and data on knowledge and attitudes concerning the risks and prevention of consanguineous marriage were obtained using an online self-administered questionnaire. The factors associated with good knowledge and attitude toward consanguineous marriage were investigated by logistic regression analysis.

RESULTS

A total of 667 participants enrolled in the study. The average knowledge score about consanguineous marriage risk and prevention was 78.6% with a 95% confidence interval (CI) [77.3, 79.8], and the average attitude was 79.7% with a 95% confidence interval (CI) [79, 80.6]. A better knowledge score was observed in older participants (OR 1.01; 95% CI 1.004-1.024), females (OR 1.69; 95% CI 1.48-1.94), participants with parental history of consanguinity (OR 1.33; 95% CI 1.17-1.52), participants with family history of consanguineous marriage (OR 5.18; 95% CI 2.19-7.10), and participants with family history of inherited disease (OR 1.52; 95% CI 1.25-1.86).

CONCLUSION

In general, the overall level of knowledge and attitudes toward consanguineous marriage risk and prevention was good among university students. To efficiently control and manage the adverse health impacts associated with consanguineous marriage, there is an urgent need to develop and implement evidence-based counseling and screening programs for consanguineous marriage that would significantly reduce the number of at-risk marriages.

Assessment of Novel Inhaler Technique Reminder Labels in Image Format on the Correct Demonstration of Inhaler Technique Skills in Asthma: A Single-Blinded Randomized Controlled Trial

BACKGROUND

Prevalence of asthma in the United Arab Emirates (UAE) is high, and training patients on correct inhaler technique is vital.

OBJECTIVES

To assess the effectiveness of inhaler technique labels incorporating the individual technique steps in image format on the retention of correct inhaler technique for patients with asthma living in the UAE and following inhaler training; secondly to investigate the effect of inhaler technique education using self-check pictorial labels on patients' overall asthma control.

METHODS

This single-blinded randomized controlled study was conducted in 2019 and followed consecutive recruitment of asthma patients visiting respiratory clinics at Rashid Hospital in Dubai. Patients were using a controller inhaler (Turbuhaler (TH), Accuhaler (ACC), or pressurized metered-dose inhaler (pMDI)). Following recruitment, patients were randomized into active group receiving educational intervention plus the inhaler label, and control group receiving educational intervention without the label. Patients were assessed at baseline and at one-month on their inhaler technique and asthma control.

RESULTS

Participants (n = 245; 93 = TH, 70 = ACC, 82 = pMDI) showed a significant difference between the groups at one-month for inhaler technique scores for TH (active 5.29 ± 1.86 vs. control = 24.4 ± 21.28), ACC (active = 3.99 ± 1.43 vs. control = 25.45 ± 22.57), and pMDI (active = 4.59 ± 0.10 vs. control = 120.55 ± 17.2), p < 0.001 for all. Asthma control for active group indicated significant improvements compared to control for TH and pMDI (p < 0.001 for both), but not ACC group (p = 0.087).

CONCLUSIONS

Retention of correct inhaler technique and improved asthma control can be enhanced by using a specialized inhaler technique label in image format.

A specialized training program on inhaler technique delivered by pharmacists to nurses: a study from the United Arab Emirates

Background

Inhaled drug delivery has been hailed as a major advancement in respiratory therapeutics. However, a major limitation to use the inhaled medications effectively is the inability of patients and nurses to use and demonstrate the proper use of these devices correctly. Being the drug experts, pharmacists are in a pivotal position to delivered tailored education to their peers, the nurses.

Aim

This study aims to examine nurses' knowledge of asthma management, their ability to demonstrate proper inhaler technique, and the impact of a specialized workshop training program delivered by skilled pharmacists on improving their performance.

Methods

This is a pre- and post-cross-sectional study design in hospital setting where nurses were recruited from the respiratory and emergency departments within a healthcare facility in the United Arab Emirates (UAE). The nurses attended a training workshop prepared and delivered by skilled pharmacists on inhaler technique demonstration skills. Nurses' inhaler technique demonstration skills for Diskus, Turbuhaler, and pMDI were assessed at baseline, immediately after the workshop, and after four weeks. The nurses completed the demographic and Asthma Knowledge Questionnaire (AKQ).

Results

A random convenience sample of registered nurses (n=20) from the respiratory and emergency departments was recruited from a tertiary hospital in Sharjah, UAE, with a mean age of 35.25 (SD=6.96) years, of whom 90% were females. The mean number of years of experience was 12.00 years (SD=5.81). Inhaler technique assessment revealed low inhaler technique scores for all the three study inhalers at baseline (mean score for Diskus=3.85 (SD=2.87); Turbuhaler=3.70 (SD=3.20); pMDI=4.50 (SD=2.65)) Significant improvements in inhaler technique scores were noted after the workshop (Diskus=8.9 (SD=0.31); Turbuhaler=8.9 (SD=0.31); pMDI=8.0 (SD=0.00), P<0.001). A significant difference in AKQ scores was found before (mean=4.85 (SD=1.27)) and after (mean=7.50 (SD=0.95)) the workshop training session (P<0.001), and four weeks after the workshop training session (mean=7.55 (SD=0.76), P<0.001).

Conclusion

The UAE nurses' inhaler technique and AKQ scores were suboptimal at baseline. The specialized training program prepared and delivered by the skilled pharmacists improved nurses' inhaler technique demonstration skills and AKQ scores. Such improvements would reflect positively on patients' asthma management outcomes as nurses are the health care professionals who interact the most with the patients during hospitalization.