Delta Variant in the COVID-19 Pandemic: A Comparative Study on Clinical Outcomes Based on Vaccination Status

BACKGROUND

As the global battle against the COVID-19 pandemic endures, the spread of the Delta variant has introduced nuanced challenges, prompting a nuanced examination.

MATERIALS AND METHODS

We performed a multilevel logistic regression analysis encompassing 197 patients, comprising 44 vaccinated individuals (V group) and 153 unvaccinated counterparts (UV). These patients, afflicted with the Delta variant of SARS-CoV-2, were hospitalized between October 2021 and February 2022 at the COVID-19 department of a University Centre in Cluj-Napoca, Romania. We compared patient characteristics, CT lung involvement, Padua score, oxygen saturation (O2 saturation), ventilation requirements, dynamics of arterial blood gas (ABG) parameters, ICU admission rates, and mortality rates between the two groups.

RESULTS

The UV group exhibited a statistically significant (p < 0.05) proclivity toward developing a more severe form of infection, marked by elevated rates of lung involvement, oxygen requirement, ICU admission, and mortality.

CONCLUSION

Our findings underscore the substantial efficacy of the vaccine in diminishing the incidence of severe disease, lowering the rates of ICU admissions, and mitigating mortality among hospitalized patients.

The Effects of Probiotic Bacillus Spores on Dexamethasone-Treated Rats

Glucocorticoids are effective anti-inflammatory and immunosuppressive agents. Long-term exposure is associated with multiple metabolic side effects. Spore-forming probiotic bacteria have shown modulatory properties regarding glycolipid metabolism and inflammation. The aim of this study was to evaluate, for the first time, the effects of Bacillus species spores (B. licheniformis, B. indicus, B. subtilis, B. clausii, and B. coagulans) alone and in combination with metformin against dexamethasone-induced systemic disturbances. A total of 30 rats were randomly divided into 5 groups: group 1 served as control (CONTROL), group 2 received dexamethasone (DEXA), group 3 received DEXA and MegaSporeBiotic (MSB), group 4 received DEXA and metformin (MET), and group 5 received DEXA, MSB, and MET. On the last day of the experiment, blood samples and liver tissue samples for histopathological examination were collected. We determined serum glucose, total cholesterol, triglycerides, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10), catalase, total antioxidant capacity (TAC), and metformin concentration. DEXA administration caused hyperglycemia and hyperlipidemia, increased inflammation cytokines, and decreased antioxidant markers. Treatment with MSB reduced total cholesterol, suggesting that the administration of Bacillus spores-based probiotics to DEXA-treated rats could ameliorate metabolic parameters.

The Psoriasis Disability Index in Romanian Psoriasis Patients during COVID-19 Pandemic: Contribution of Clinical and Psychological Variables

BACKGROUND

Psoriasis is one of the most frequent chronic inflammatory skin diseases and has a negative impact on the interpersonal relationship and psychosocial well-being. The aims of this study were to examine the effects of intensity of pruritus on quality of life and depression, to investigate the relationship between anger, self-esteem, and depression, and to compare patients with early and late onset of psoriasis. As our study was carried out during the COVID-19 pandemic, we aimed also to investigate the safety concerns and anxiety related to COVID-19 in psoriasis patients.

METHODS

This cross-sectional study included 137 patients diagnosed with plaque psoriasis. The patients were classified as early-onset (age < 30 years) and late-onset psoriasis (age ≥ 30 years). Duration of disease, pruritus scores, and socio-demographic characteristics were recorded. Measures included the State-Trait Anger Expression Inventory (STAXI), Rosenberg Self-Esteem Scale, Beck Depression Inventory (BDI-II), Psoriasis Disability Index (PDI), and Fear and anxiety in relationship with COVID-19 Scale were used for determining anger, anger expression style, self-esteem, depression, anxiety, and quality of life.

RESULTS

The psoriasis patients had a lower score for self-esteem than the normative data from the Romanian general population. The average scores for state anger and trait anger are similar to the normative data from the Romanian general population, but the scores for anger-in and anger-out are higher. Patients with early onset had higher depression scores and lower quality of life. Self-esteem correlates negatively with depression, anger, severity of disability due to psoriasis, number of affected areas, and duration of disease. Lower level of self-esteem led to increased anger.

CONCLUSIONS

Reduced self-esteem, increased anger levels, and depression are present in psoriasis patients. The effective treatment of psoriasis must, therefore, consist of a multidisciplinary approach, in which the personalized treatment of the skin condition is as important as the adjuvant therapies that reduce the patients' stress level.

Gastrointestinal microbiota: A predictor of COVID-19 severity?

Coronavirus disease 2019 (COVID-19), caused by a severe acute respiratory syndrome coronavirus 2 infection, has raised serious concerns worldwide over the past 3 years. The severity and clinical course of COVID-19 depends on many factors (e.g., associated comorbidities, age, etc) and may have various clinical and imaging findings, which raises management concerns. Gut microbiota composition is known to influence respiratory disease, and respiratory viral infection can also influence gut microbiota. Gut and lung microbiota and their relationship (gut-lung axis) can act as modulators of inflammation. Modulating the intestinal microbiota, by improving its composition and diversity through nutraceutical agents, can have a positive impact in the prophylaxis/treatment of COVID-19.

Therapeutic Efficacy and Outcomes of Remdesivir versus Remdesivir with Tocilizumab in Severe SARS-CoV-2 Infection

The infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) generated many challenges to find an effective drug combination for hospitalized patients with severe forms of coronavirus disease 2019 (COVID-19) pneumonia. We conducted a retrospective cohort study, including 182 patients with severe COVID-19 pneumonia hospitalized between March and October 2021 in a Pneumology Hospital from Cluj-Napoca, Romania. Among patients treated with standard of care, 100 patients received remdesivir (R group) and 82 patients received the combination of remdesivir plus tocilizumab (RT group). We compared the clinical outcomes, the inflammatory markers, superinfections, oxygen requirement, intensive care unit (ICU) admission and mortality rate before drug administration and 7 days after in R group and RT group. Borg score and oxygen support showed an improvement in the R group (p < 0.005). Neutrophiles, C-reactive protein (CRP) and serum ferritin levels decreased significantly in RT group but with a higher rate of superinfection in this group. ICU admission and death did not differ significantly between groups. The combination of remdesivir plus tocilizumab led to a significantly improvement in the inflammatory markers and a decrease in the oxygen requirement. Although the superinfection rate was higher in RT group than in R group, no significant difference was found in the ICU admission and mortality rate between the groups.

Duodenal Ampulla Neuroendocrine Tumor with GISTs of the Proximal Jejunum: A Case Report

Neuroendocrine tumors (NEN) are a type of heterogenous, slow-growing tumors, that only in about half of the cases can be found in the gastrointestinal tract. Half of these is in the small intestine. The ampullary NENs are rare, accounting for less than 1% of gastroenteropancreatic NENs. Gastrointestinal stromal tumors (GIST) are a more common type of tumors of the gastrointestinal tract that consist of pacemaker cells. The occurrence of both tumors simultaneously is rare, but in patients with neurofibromatosis type 1, the co-existence of NEN and GIST is more often. Here we report a case of simultaneous occurrence of a well-differentiated NEN and a GIST in a patient without neurofibromatosis. Also, we provide a short review of the current knowledge and treatment strategies regarding these tumors.

Curcumin-Loaded Microspheres Are Effective in Preventing Oxidative Stress and Intestinal Inflammatory Abnormalities in Experimental Ulcerative Colitis in Rats

Curcumin’s role in the treatment of ulcerative colitis (UC) has been proven by numerous studies, but its preventive administration, with the aim of reducing the remission episodes that are characteristic of this disease, must be further investigated. This study investigates the effects of a novel curcumin-loaded polymeric microparticulate oral-drug-delivery system for colon targeting (Col-CUR-MPs) in an experimental model of UC. Male Wistar rats (n = 40) were divided into five groups (n = 8), which were treated daily by oral gavage for seven days with a 2% aqueous solution of carboxymethylcellulose sodium salt (CMCNa) (healthy and disease control), free curcumin powder (reference), Col-CUR-MPs (test) and prednisolone (reference) prior to UC induction by the intrarectal administration of acetic acid (AA), followed by animal sacrification and blood and colonic samples’ collection on the eighth day. Col-CUR-MPs exhibited an important preventive effect in the severity degree of oxidative stress that resulted following AA intrarectal administration, which was proved by the highest catalase (CAT) and total antioxidant capacity (TAC) levels and the lowest nitrites/nitrates (NOx), total oxidative status (TOS) and oxidative stress index (OSI) levels. Biochemical parameter analysis was supported by histopathological assessment, confirming the significant anti-inflammatory and antioxidant effects of this novel colon-specific delivery system in AA-induced rat models of UC. Thus, this study offers encouraging perspectives regarding the preventive administration of curcumin in the form of a drug delivery system for colon targeting.

Novel concepts in psoriasis: histopathology and markers related to modern treatment approaches

Psoriasis is a chronic autoimmune disease affecting over 2% of the worldwide population. From an anatomopathological point of view, psoriasis is characterized by immune cells infiltration, epidermal hyperproliferation, and abnormal keratinocyte differentiation. Understanding the pathogenesis of psoriasis will allow clinicians to manage this complex disease. Under these conditions, the application of effective treatments requires a thorough knowledge of all the pathogenetic mechanisms that lead to psoriasis. Numerous immunopathological pathways play crucial roles in the development of new therapies, such as biological therapies, which have been a breakthrough in psoriasis’s treatment. Pharmacogenetics is an essential factor in the patient’s response to treatment. One important pathway targeted by modern treatments is the interleukin (IL)-23/T-helper (Th)17 axis. Like IL-17 inhibitors, IL-23 blockers are a very effective therapy for this autoimmune disease. It is considered that micro-ribonucleic acids (microRNAs) are the starting point for any autoimmune disease. Studying certain microRNA (miR) involved in the inflammatory pathway in psoriasis can find direct targets to future treatments that can even be more specific than actual biological therapies. As such, miR-210 has proven to be up-regulated in psoriasis, also leading to the up-regulation of the Th1/Th17 axis. On the other hand, miR-187 was found to be down-regulated, influencing the outcome of psoriasis by increasing the proliferation of IL-6 stimulated keratinocytes and consecutively generating epidermal thickening. In this review, we are aiming to do an up-to-date briefing of psoriasis histopathology and pharmacogenetic factors that are considered for the accurate evaluation of treatment response.

Overview of the microbiota in the gut-liver axis in viral B and C hepatitis

Viral B and C hepatitis are a major current health issue, both diseases having a chronic damaging effect on the liver and its functions. Chronic liver disease can lead to even more severe and life-threatening conditions, such as liver cirrhosis and hepatocellular carcinoma. Recent years have uncovered an important interplay between the liver and the gut microbiome: the gut-liver axis. Hepatitis B and C infections often cause alterations in the gut microbiota by lowering the levels of ‘protective’ gut microorganisms and, by doing so, hinder the microbiota ability to boost the immune response. Treatments aimed at restoring the gut microbiota balance may provide a valuable addition to current practice therapies and may help limit the chronic changes observed in the liver of hepatitis B and C patients. This review aims to summarize the current knowledge on the anato-functional axis between the gut and liver and to highlight the influence that hepatitis B and C viruses have on the microbiota balance, as well as the influence of treatments aimed at restoring the gut microbiota on infected livers and disease progression.

Ultrasound Image Computerized Analysis for Non-invasive Quantitative Evaluation of Hepatic Fibrosis

BACKGROUND

Assessing the diagnostic value of liver ultrasound image computerized analysis (USICA) for hepatic fibrosis (HF) staging in respect to the "gold standard" provided by liver biopsy (LB).

METHODS

Two-hundred twenty-eight patients with chronic hepatopathies were prospectively enrolled in the study. All the patients underwent LB and abdominal ultrasound (US). For quantitative US assessment of HF, an image analysis software was developed and 3 parameters were extracted by wavelet processing of the region of interest: mHLlivermHHliver, mHLlivermLLliver, and mHLlivermHLspleen. To assess the relevance of each feature, the support vector machine (SVM) classifiers were employed to discriminate between the 2 severity classes (i.e., incipient F1-F2 vs advanced F3-F4 fibrosis). The statistical significance of the HF staging was assessed using SVM classifiers, in terms of sensitivity (Se), specificity (Sp), and receiver operating characteristic (ROC) curves.

RESULTS

A cut-off value of 0.342 of mHLlivermHHliver allowed the discrimination between the incipient and advanced HF with 79.5% Se and 77.4% Sp, at an area under receiver operating characteristic (AUROC) value of 0.867 (P < .001).

CONCLUSION

The proposed USICA using wavelet filter parameters proved to be an innovative method that is useful for the initial noninvasive evaluation and quantification of HF, with the advantages of simplicity, short calculation time, accessibility, and repeatability. The mHLlivermHHliver parameter has demonstrated good accuracy in distinguishing incipient and advanced HF and can be considered an effective non-invasive imaging marker for the assessment of HF in patients with chronic hepatic disease.

Assessment of mismatch repair deficiency, CDX2, beta-catenin and E-cadherin expression in colon cancer: molecular characteristics and impact on prognosis and survival - an immunohistochemical study

Microsatellite instability (MSI) or the deficiency of mismatch repair (MMR) proteins is one of the molecular pathways of colorectal tumorigenesis and may have important clinical implications in predicting the treatment response. We evaluated the relationship between clinicopathological features and MMR proteins [mutL homologue 1 (MLH1), mutS homologue 2 (MSH2), mutS homologue 6 (MSH6), postmeiotic segregation increased 2 (PMS2)], adhesion molecules (E-cadherin, beta-catenin) and caudal-type homeobox 2 (CDX2) in 31 patients with colon adenocarcinoma, using immunohistochemistry. We also aimed to assess the prognostic value of the studied proteins. MLH1 loss was correlated to PMS2 loss (p=0.006) and MSH2 loss (p=0.023); MSH2 loss was significantly associated to MSH6 loss (p=0.011). Tumors with MSH6 loss, together with tumors with PMS2 loss, covered all the patients with MSI status. We found a significant correlation between MSI tumors and mucinous histological type (p=0.03), but no significant associations with other clinicopathological features or with survival rate. There was a significant correlation between E-cadherin expression and differentiation degree (p=0.018) and between beta-catenin expression and lymph node invasion (p=0.046). No significant association between CDX2 loss and any clinical or pathological features was found (p>0.05). No significant differences were identified in overall survival according to E-cadherin, beta-catenin or CDX2 expression (p>0.05). In our study, PMS2 loss was significantly correlated with CDX2 loss (p=0.03). In conclusion, the molecular analysis of biological markers for colon cancer may be important for patient stratification, in order to select the optimal treatment algorithm. Our results suggest that probably the double panel (MSH6 and PMS2) is enough to detect the MSI status, instead of using the quadruple panel.

Probiotic Bacillus Spores Together with Amino Acids and Immunoglobulins Exert Protective Effects on a Rat Model of Ulcerative Colitis

In inflammatory bowel disease (IBD), experimental models have proven to be important tools for evaluating potential therapeutic agents and for investigating the mechanisms of pathogenesis. Oxidative stress and the immune response have been associated with acetic acid (AA)-induced ulcerative colitis (UC). Our study aimed to evaluate, for the first time, the ability of a spore-based probiotic and an amino acid and immunoglobulin supplement in reducing tissue damage and inflammatory responses in an experimental animal model of UC. Forty-two Wistar rats were divided into six groups, receiving 1% carboxymethylcellulose, 4% AA, MegaSporeBiotic™ (MSB; 1 × 10⁹ colony forming units/day) and MegaMucosa™ (MM; 70 mg/100 g/day). Pretreatment with MSB or MM alone and in combination significantly lowered inflammation and reduced damage to the colonic mucosa. Pretreatment with these agents resulted in levels of proinflammatory cytokines, vascular tight junction proteins, and measures of oxidative stress similar to those reported for methylprednisolone, one of the first-line therapies for moderate to severe activity of UC. The protection was further confirmed by histologic analysis of the colon tissue. In conclusion, pretreatment with probiotic spore-forming Bacillus strains and a supplement of amino acids in combination with immunoglobulins exhibited anti-inflammatory and antioxidant effects in an AA-induced rat model of UC.

Probiotic Bacillus Spores Protect Against Acetaminophen Induced Acute Liver Injury in Rats

Acetaminophen (APAP) is one of the most used analgesics and antipyretic agents in the world. Intoxication with APAP is the main cause of acute liver toxicity in both the US and Europe. Spore-forming probiotic bacteria have the ability to resist harsh gastric and intestinal conditions. The aim of this study was to investigate the possible protective effect of Bacillus (B) species (sp) spores (B. licheniformis, B. indicus, B. subtilis, B. clausii, B. coagulans) against hepatotoxicity induced by APAP in rats. A total of 35 rats were randomly divided into seven groups: group I served as control; group II received silymarin; group III received MegaSporeBiotic^TM (MSB); group IV received APAP and served as the model of hepatotoxicity; group V received APAP and silymarin; group VI received APAP and MSB; group VII received APAP, silymarin and MSB. The livers for histopathological examination and blood samples were collected on the last day of the experiment. We determined aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total antioxidant capacity (TAC) levels and zonula occludens (ZO-1), tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) expression. APAP overdose increased AST and ALT. It slowly decreased TAC compared to the control group, but pretreatment with silymarin and MSB increased TAC levels. Elevated plasma concentrations were identified for ZO-1 in groups treated with APAP overdose compared with those without APAP or receiving APAP in combination with silymarin, MSB or both. The changes were positively correlated with the levels of other proinflammatory cytokines (TNF-α, IL-1β). In addition, histopathological hepatic injury was improved by preadministration of MSB or silymarin versus the disease model group. Bacillus sp spores had a protective effect on acute hepatic injury induced by APAP. Pretreatment with MSB resulted in a significant reduction in serum AST, ALT, TNF-α, IL-1β, ZO-1, TAC and also hepatocyte necrosis, similar to the well-known hepatoprotective agent—silymarin.

Microbiota and Immune-Mediated Skin Diseases-An Overview

In recent years, increased attention has been paid to the relationship between microbiota and various diseases, especially immune-mediated diseases. Because conventional therapy for many autoimmune diseases is limited both in efficacy and safety, there is an increased interest in identifying nutraceuticals, particularly probiotics, able to modulate the microbiota and ameliorate these diseases. In this review, we analyzed the research focused on the role of gut microbiota and skin in immunity, their role in immune-mediated skin diseases (IMSDs), and the beneficial effect of probiotics in patients with this pathology. We selected articles published between 2009 and 2019 in PubMed and ScienceDirect that provided information regarding microbiota, IMSDs and the role of probiotics in these diseases. We included results from different types of studies including observational and interventional clinical trials or in vivo and in vitro experimental studies. Our results showed that probiotics have a beneficial effect in changing the microbiota of patients with IMSDs; they also influence disease progression. Further studies are needed to better understand the impact of new therapies on intestinal microbiota. It is also important to determine whether the microbiota of patients with autoimmune diseases can be manipulated in order to restore homeostasis of the microbiota.

The advantages of water immersion colonoscopy in ambulatory service

BACKGROUND/AIMS

The purpose of this prospective study was to compare patients' discomfort during water immersion (WI) colonoscopy without sedation or available on request, with that of patients during air insufflation (AI) colonoscopy with sedation, in the ambulatory setting.

MATERIAL AND METHODS

A prospective observational study was conducted in 100 patients who performed a colonoscopy between August 2015 and February 2016 in an Ambulatory Gastroenterology Center in Cluj-Napoca, Romania. They were divided into two branches A and B. Patients in Group A underwent a classic colonoscopy with AI and standard sedation (2 mg of midazolam and 50 mg of tramadol), while patients in Group B underwent an unsedated or on demand sedation colonoscopy with WI technique.

RESULTS

The patients in group A presented a higher discomfort (statistically significant) compared to those in group B, and had also the median total discomfort score higher than those in group B. The patients in group A had also a higher discomfort score after examination. The total time of examination was the same in the two groups, but in group B the progression to cecum time was 3 minutes lower than for those in group A. A greater discomfort of the patient was correlated with the longer time required to reach the cecum.

CONCLUSION

In conclusion, WI colonoscopy is superior to AI technique in reducing insertion pain, progression-to-cecum time, minimizing sedation requirements and also in the willingness to repeat the technique.

Influence of concomitant medication on plasma concentration of amiodarone in patients with atrial fibrillation - a pilot study

Background

Although amiodarone is a drug with many side effects, it is one of the most commonly used drugs in the treatment and prophylaxis of supraventricular and ventricular arrhythmias.

Aim

The purpose of this pilot study was to evaluate plasma concentrations of amiodarone in patients with atrial fibrillation (AF) and to identify possible drug-drug interactions between amiodarone and concomitant medications.

Method

A prospective observational study was conducted in 27 consecutive patients treated with amiodarone from May to July 2017 in a Clinical University Hospital. The patients included met our inclusion criteria. HPLC-UV was the device used to determine the plasma concentration of amiodarone.

Results

Only 51.8% of the patients had amiodarone plasma concentration within therapeutic interval (500–2500 ng/ml). The drugs associated to amiodarone in the therapeutic plan were diuretics, beta blockers, statins, antiplatelets, fluoroquinolones, non-steroidal anti-inflammatory drugs. We observed a statistically significant difference between the plasmatic concentrations of amiodarone in patients treated with furosemide vs. patients concomitantly treated with other drugs. Interactions between other mentioned drugs and amiodarone were not registered. We can report an underuse of amiodarone for more than 50% of the patients. Also, we found a significant interaction between furosemide and amiodarone, most likely through the interaction with MDR.

Conclusion

Furosemide may influence the pharmacokinetics of P-gp-interfering drugs. However, the relevance of these findings needs to be confirmed and further research is needed to characterize the interaction between amiodarone and furosemide.

Effects of Berberis vulgaris Extract on Lipid Profile, Kidney and Liver Function in Experimental Dyslipidemia

The ability of Berberis vulgaris bark extract (BVE) to improve the lipid profile was evaluated in an experimental model of dyslipidemia, along with its effects on liver and kidney functions. Fifty rats divided into five groups of ten animals each were fed with normal or lard-based diet and orally treated with 0.9% saline solution, atorvastatin (2.5 mg/kg per body weight) or extract of BVE (300 and 500 mg/kg/day) for eight weeks. Lipid profile, liver and renal functions were assessed in normal and diet-induced hypercholesterolemic rats. The results were compared between the groups treated with Berberis extract and the group without treatment, respectively that one treated with the standard drug (atorvastatin). Administration of BVE or atorvastatin significantly decreases the elevated serum lipid profile (p [0.05). The extract also protects against dyslipidemia-induced non-alcoholic fatty liver disease (NAFLD). The activities of the plant extract are dose dependent and it compares favorably with the standard drug atorvastatin. Variations in aspartate aminotransferase (AST), alanine aminotransferase (ALT), and urea level measurements were neither different between the two determinations nor between groups, but creatinine values decreased in rats in the BVE or atorvastatin-treated groups. The findings of the current study have suggested that BVE intake suppresses the accumulation of hepatic lipids and lipid parameters and reduce the risk of NAFLD. So, BVE can be useful in hypercholesterolemia.

An overview on the interplay between nutraceuticals and gut microbiota

Background

Nowadays, growing attention was being given to the alternative ways to prevent or treat diseases. Nutraceuticals are used increasingly for this purpose. Many of these are being used as alternative therapy. Classic therapy with synthetic drugs, although very effective, has many side effects. The term “nutraceuticals” refers to the link between the nutritional and pharmaceutical domains. Also, lately, many studies have been done to investigate the role of microbiota in maintaining health. There is the hypothesis that some of the health benefits of nutraceuticals are due to their ability to change the microbiota. The aim of this review was to emphasize the link between the most commonly used nutraceuticals, the microbiota and the health benefits.

Methods

We selected the articles in PubMed, published up to July 2017, that provided information about most used nutraceuticals, microbiota and health benefits. In this review, we incorporate evidence from various types of studies, including observational, in vitro and in vivo, clinical studies or animal experiments.

Results

The results demonstrate that many nutraceuticals change the composition of microbiota and can interfere with health status of the patients.

Discussion

There is evidence which sustains the importance of nutraceuticals in people’s health through microbiota but further studies are needed to complete the assessment of nutraceuticals in health benefit as a consequence of microbiota’s changing.

Inhibitory Effect of Citalopram on the Pharmacokinetics of Carvedilol in Rats and in vitro Models

BACKGROUND/AIMS

The aim of this study was to investigate the drug-drug interaction between carvedilol and citalopram based on carvedilol metabolism in vitro and his pharmacokinetics (PKs) in vivo after the oral administration of the single drug and both drugs, and reveal citalopram effects on the PKs of carvedilol.

METHODS

Each rat was cannulated on the femoral vein, prior to being connected to BASi Culex ABC®. Carvedilol was orally administrated in rats (3.57 mg/kg body weight [b.w.]) in the absence of citalopram or after a pre-treatment with multiple oral doses of citalopram (1.42 mg/kg b.w.). Plasma concentrations of carvedilol were determined using high-performance liquid chromatography-MS at the designated time points after drug administration, and the main PK parameters were calculated by noncompartmental analysis. In addition, effects of citalopram on the metabolic rate of carvedilol were investigated using rat-pooled liver microsome incubation systems.

RESULTS

During co-administration, significant increases of the area under the plasma concentration-time curve as well as of the peak plasma concentration were observed. The rat-pooled liver microsome incubation experiment indicated that citalopram could decrease the metabolic rate of carvedilol.

CONCLUSION

Citalopram co-administration led to a significant alteration of carvedilol's PK profile in rats; it also demonstrated, in vitro, these effects could be explained by the existence of a drug-drug interaction mediated by CYP2D6 inhibition.

The Pharmacokinetic Interaction Study between Carvedilol and Bupropion in Rats

BACKGROUND/AIMS

The effects of multiple-dose bupropion on the pharmacokinetics of single-dose carvedilol were investigated in order to evaluate this possible drug-drug interaction.

METHODS

A preclinical study was conducted among white male Wistar rats. Each rat was cannulated on the femoral vein prior to being connected to BASi Culex ABC®. During the reference period, each rat received an intravenous and an oral dose of 3.57 mg/kg body weight (b.w.) carvedilol, at 2 days distance. After 5 days of pretreatment with 21.42 mg/kg b.w. bupropion (by oral route, twice a day - given in order to reach the steady state), during the sixth day, 3.57 mg/kg b.w. carvedilol and 21.42 mg/kg b.w. bupropion were orally co-administrated (test period). After each administration of carvedilol, several samples of 200 µL blood were collected. The pharmacokinetic parameters of carvedilol were analyzed by the noncompartmental method.

RESULTS

The 5 days pretreatment with bupropion increased the exposure to carvedilol in rats by 180%, considering the modifications observed in the area under the curve of carvedilol. Carvedilol was shown to have higher plasma concentrations, delay in maximum concentration, and a prolonged half-life, after being pretreated with bupropion.

CONCLUSION

The administration of multiple-dose bupropion influences the pharmacokinetics of carvedilol (single oral dose) in rats.