Research Methods in Life Sciences Commons^™

Lovastatin Potentiates The Function Of Α7-Nicotinic Acetylcholine Receptors, Dmytro Isaev, Keun-Hang Susan Yang, Murat Oz

Pharmacy Faculty Articles and Research

Background/Objectives: Statins are currently one of the most commonly used cholesterol-lowering drugs. In recent years, in addition to their well-known effects on the cardiovascular system, statins have been shown to exert beneficial effects in the progression of various neuropsychiatric and neurodegenerative diseases. Methods: In this study, the effects of lovastatin on the function of α7-nicotinic acetylcholine (nACh) receptors expressed in rat hippocampus and Xenopus oocytes were investigated. Results: In whole-cell patch clamp studies in hippocampal neurons, 21-day chronic (20 mg/kg), but not acute (20 min), lovastatin treatment caused significant potentiation of choline (a selective agonist for α7 nACh receptors)-induced currents …

Effects Of Normothermic Hepatic Ischemia–Reperfusion Injury On The Hepatic Disposition Of Arachidonic Acid And Its Cytochrome P450-Generated Metabolites In Rats, Vindhya Edpuganti, Reza Mehvar

Pharmacy Faculty Articles and Research

Purpose

Cytochrome P450 (P450) metabolites of arachidonic acid (AA) are potential therapeutic targets in ischemia–reperfusion (IR) injury, yet their disposition and actions in hepatic IR are unknown. Cellular AA and its P450 metabolites are primarily bound to lipid membranes, resulting in negligible free concentrations. This study investigates how hepatic IR injury impacts the disposition of free AA and its major P450 metabolites in rats.

Methods

Rats underwent 60 min of partial (70%) ischemia or sham surgery, followed by 5 min, 3 h, or 24 h of reperfusion. The effects of IR injury on free concentrations of AA and its major …

Hepatocyte-Specific Lrp1 Silencing Exacerbates Brain Amyloidosis Without Compensatory Ldl Receptor Family Involvement, Brian Carson, Josephine Chu, Devaraj V. Chandrashekar, Jerome Garcia, Rachita K. Sumbria, Derick Han

Pharmacy Faculty Articles and Research

Background

LDL receptor related protein 1 (LRP1) is a major hepatic receptor involved in lipoprotein metabolism, protease degradation, transmembrane receptor modulation, and clearance of excess protein, such as Aβ. Decreased expression of LRP1 due to liver injury can impair receptor-mediated clearance, increasing Aβ availability in the periphery. We investigated the effects of hepato-specific silencing of LRP1 on Aβ deposition in the brain. Additionally, other LDL family members (LRP5, LRP6, and LDLR) that may participate in Aβ clearance were monitored in the liver to ensure non-compensatory effects of LRP1 silencing.

Method

4-month-old male double transgenic (APP/PS1) AD mice were injected with …

The Mitochondria Is The Source Of Hepatic Amyloid Precursor Protein And Peripheral Amyloid Beta: Implications Of Alcohol-Induced Liver Steatosis In Alzheimer's Disease, Josephine Chu, Ross A. Steinberg, Brian Carson, Devaraj Venkatapura Chandrashekar, Rachita K. Sumbria, Derick Han

Pharmacy Faculty Articles and Research

Background

Alcohol-induced liver injury occurs in the pericentral region of the liver and can induce mitochondrial remodeling and exacerbate Alzheimer's Disease (AD) progression. Subpopulations of mitochondria: general mitochondria (GM), peridroplet mitochondria (PDM) and endoplasmic reticulum(ER)-bound mitochondria (ERM) maintain cellular homeostasis via energy synthesis, lipid homeostasis, and regulation of intracellular calcium. Hepatic amyloid precursor protein (APP) is a source of peripheral amyloid beta (aB) and affects AD pathology in the brain. Understanding the localization and expression of hepatic APP in mitochondrial subpopulations are critical to understanding aB metabolism and may play a role in identifying a potential mechanism for metabolic dysfunction. …

Longitudinal Pharmacokinetic And Safety Studies Of An Antibody-Erythropoietin Fusion Protein For Alzheimer's Disease, Rudy Chang, Devaraj Venkatapura Chandrashekar, G. Chuli Roules, Nataraj Jagadeesan, Emi Iwasaki, Adenike Oyegbesan, Hayk Davtyan, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Erythropoietin (EPO) shows promise for Alzheimer's disease (AD) but has poor brain penetration, necessitating high doses that cause hematopoietic side effects. To improve brain delivery, EPO was fused to a transferrin receptor monoclonal antibody (TfRMAb), and this study evaluated the pharmacokinetics (PK), safety, and efficacy of repeated TfRMAb-EPO dosing in mice to further its preclinical development. C57BL/6J male mice (10 weeks old, n = 4–5/dose) received subcutaneous (SQ) low (1 mg/kg), mid (3 and 6 mg/kg), or high (20 mg/kg) TfRMAb-EPO doses for 4 weeks. The 1 mg/kg dose showed no adverse effects and resulted in sustained brain and plasma …

Citronellol Reduces Sepsis-Induced Renal Inflammation Via Ap-1/Nf-Κb/Tnf-Α Pathway, Huda Rashid Atiyah, Sarmed H. Kathem, Surya M. Nauli

Pharmacy Faculty Articles and Research

Sepsis is characterized by the over-production of pro-inflammatory cytokines. Cecal ligation and puncture (CLP) is a well-accepted model for recreating sepsis-induced renal injury in mice. The current study investigates how citronellol, a naturally occurring substance with a variety of biological characteristics, can prevent acute kidney inflammation brought on by CLP. In the CLP mouse model, citronellol was administered orally at doses of 50 and 100 mg/kg. Serum levels of creatinine and urea were used as markers of renal function, and the Murine Sepsis Score (MSS) was used to assess the severity of sepsis. According to our findings, CLP caused a …

Cilia In The Brain Display Region-Dependent Oscillations Of Length And Orientation, Roudabeh Vakil Monfared, Sherif Abdelkarim, Pieter Derdeyn, Kiki Chen, Hanting Wu, Kenneth Leong, Tiffany Chang, Justine Lee, Sara Versales, Surya M. Nauli, Kevin Beier, Pierre Baldi, Amal Alachkar

Pharmacy Faculty Articles and Research

In this study, we conducted high-throughput spatiotemporal analysis of primary cilia length and orientation across 22 mouse brain regions. We developed automated image analysis algorithms, which enabled us to examine over 10 million individual cilia, generating the largest spatiotemporal atlas of cilia. We found that cilia length and orientation display substantial variations across different brain regions and exhibit fluctuations over a 24-h period, with region-specific peaks during light-dark phases. Our analysis revealed unique orientation patterns of cilia, suggesting that cilia orientation within the brain is not random but follows specific patterns. Using BioCycle, we identified rhythmic fluctuations in cilia length …

Sickle Cell Mice Exhibit Elevated Plasma Bilirubin And Altered Intracranial Cerebral Blood Velocities That Are Exacerbated By Hypoxia-Reoxygenation, Francisco J. Nunez, Ashraf M. Mohieldin, Amy Y. Pan, Sean P. Palecek, Rahima Zennadi, Ramani Ramchandran, Kevin R. Rarick, Surya M. Nauli

Pharmacy Faculty Articles and Research

Sickle cell disease (SCD) is a genetic disorder characterized by sickle red blood cells (RBCs). Sickle RBCs cause cerebral vasculopathies including vaso-occlusive events, leading to ischemia-reperfusion injury and hypoxic tissue environment. To date, the physiological blood flow velocities in cerebral vessels of preclinical SCD models has not been evaluated under hypoxic-reoxygenation. In our study, we used transcranial ultrasound techniques to measure abnormal blood flow velocities in the internal carotid (ICA) and middle cerebral arteries (MCA) of transgenic sickle cell mice (SS) challenged with hypoxia-reoxygenation. Our study showed that SS mice that underwent hypoxic stress exhibited lower relative mean velocities in …

Effect Of Chronic Alcohol Feeding Using The Lieber-Decarli Diet On Alzheimer’S Disease Pathology In Tg2576 Mice, Devaraj V. Chandrashekar, Nataraj Jagadeesan, Tamara Abdullah, Rudy Chang, Ross A. Steinberg, Frankey Sanchez, Elias Khal, Joshua Yang, David H. Cribbs, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background: Chronic alcohol drinking is a modifiable risk factor for Alzheimer’s disease (AD), but underlying mechanisms remain poorly understood. Most studies of alcohol feeding to AD mice have utilized young mice and delivered alcohol in drinking water without controlling nutritional intake.

Objective: To study the impact of Lieber-DeCarli (LDC) liquid alcohol diet, which balances nutritional intake, on AD pathology of aged Tg2576 and wild-type (WT) mice, which is unexplored.

Methods: 13-month-old male and female Tg2576 or WT mice were fed LDC diet (5% ethanol or control) for six weeks (n = 11-13/group). Exploration (open-field test) and spatial reference memory …

Brain Delivery Of Erythropoietin Results In A Significant Reduction Of Brain Aβ And Spatial Memory Deficits In The App Knock-In Mouse Model, Rudy Tieu Chang, Devaraj V. Chandrashekar, Grace-Ann Chuli Roules, Emi Iwasaki, Nataraj Jagadeesan, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Although novel treatments for Alzheimer’s disease (AD) have begun to show modest therapeutic effects, agents that target hallmark AD pathology and offer neuroprotection are desired. Erythropoietin (EPO) is a glycoprotein hormone with neuroprotective effects but is faced with challenges including limited brain uptake and increased hematopoietic side effects with long-term dosing. Therefore, EPO has been modified and bound to a chimeric transferrin receptor monoclonal antibody (cTfRMAb); the latter shuttles EPO past the blood-brain barrier (BBB) into brain parenchyma and reduces its plasma exposure and potential for side effects. Our study sought to characterize the safety and pharmacokinetics (PK) of …

Chronic Heavy Alcohol Intake And Liver-Specific Lrp-1 Reduction Increase Amyloidosis In Alzheimer’S Disease Mice, Devaraj V. Chandrashekar, G. Chuli Roules, Ross A. Steinberg, Urvashi R. Panchal, Nataraj Jagadeesan, Adenike Oyegbesan, Trinh Roselyn, Joshua Yang, Sharda R. Bhagwat, Hiya Rakholia, Rutvi D. Mevawala, Moom Roosan, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Chronic heavy alcohol drinking may be a modifiable risk factor for Alzheimer’s disease (AD), but studies in rodent AD models more closely mimic chronic moderate alcohol drinking in humans and largely focus on the brain. The role of the liver, which is significantly impacted by chronic heavy alcohol intake, in driving brain changes in alcohol-dependent AD remains unexplored. Our study using intragastric-ethanol feeding, which mimics chronic heavy alcohol intake in humans, in C57BL/6J mice showed significant AD-relevant changes in the brain and liver. Therefore, we aimed to investigate how hepatic changes using this model of chronic heavy drinking drive …

Hyperglycemia Causes Differential Change In Macrophage Population In The Lacrimal Gland, Conjunctiva And Cornea, Saleh Alfuraih, Amy Tran, Lois Kim, Rais Ansari, Ajay Sharma

Pharmacy Faculty Articles and Research

Background: Due to its location, the ocular surface is exposed to environmental microbes. Innate immune cells including macrophages are first line defense against infections. In vitro exposure to high glucose as well as diabetes-associated hyperglycemia has been shown to affect innate immune cell function and population. The present study was designed to examine the effect of diabetes-associated hyperglycemia on the lacrimal gland, conjunctiva and cornea macrophage population, phenotypic changes and cytokines/chemokines.

Methods: Mouse model of Streptozotocin-induced diabetes was used to induce hyperglycemia. Immunostaining for CD11b and F4/80 was performed to stain macrophages in whole mount cornea, conjunctiva and 50 µm …

Bile Duct Ligation-Induced Cirrhosis Does Not Alter The Blood-Brain Barrier Permeability To Sucrose In Rats, Mohammad K. Miah, Ulrich Bickel, Reza Mehvar

Pharmacy Faculty Articles and Research

Contradictory results have been reported about the effects of liver diseases on the blood-brain barrier (BBB) permeability to markers. For instance, both an increase and no change in the BBB permeability to BBB markers sodium fluorescein and Evans blue have been reported in experimental cholestasis induced by bile duct ligation (BDL) in rats. These contradictory effects might be due to inherent limitations of these markers and/or methodological issues. Here, we investigated the time course of the impact of BDL in rats on BBB permeability using a recently developed stable isotope labeled marker [¹³C]sucrose, which is expected to be …

A Protocol For Immunostaining Of Macrophages In Whole-Mount Mouse Cornea, Conjunctiva, And Lacrimal Gland, Saleh Alfuraih, Dhruv Patel, Wonsuk Choi, Karthikeyan Ramasamy, Rais Ansari, Ajay Sharma

Pharmacy Faculty Articles and Research

The healthy lacrimal functional unit contains a resident macrophage population. Here, we present a protocol for immunofluorescent staining of macrophage markers, CD11b, F4/80, and CD206, in whole-mount mouse cornea, conjunctiva, and 50-μM-thick lacrimal gland section. We describe steps for dissection, fixation, permeabilization, and blocking. We then detail procedures for the detection and spatial localization of macrophages through immunostaining and confocal imaging. This approach circumvents the need to obtain thin tissue sections and acquire macrophage images from each tissue section.

Hepatic Lrp-1 Plays An Important Role In Amyloidosis In Alzheimer's Disease Mice: Potential Role In Chronic Heavy Alcohol Feeding, Devaraj V. Chandrashekar, G. Chuli Roules, Nataraj Jagadeesan, Urvashi R. Panchal, Adenike Oyegbesan, Oghenetega E. Imiruaye, Hai Zhang, Jerome Garcia, Kamaljit Kaur, Sanda Win, Tin A. Than, Neil Kaplowitz, Moom R. Roosan, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Methods

Modulation Of Hippocampal Protein Expression By A Brain Penetrant Biologic Tnf-Α Inhibitor In The 3xtg Alzheimer’S Disease Mice, Nataraj Jagadeesan, G. Chuli Roules, Devaraj V. Chandrashekar, Joshua Yang, Sanjana Kolluru, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Biologic TNF-α inhibitors (bTNFIs) can block cerebral TNF-α in Alzheimer’s disease (AD) if these macromolecules can cross the blood–brain barrier (BBB). Thus, a model bTNFI, the extracellular domain of type II TNF-α receptor (TNFR), which can bind to and sequester TNF-α, was fused with a mouse transferrin receptor antibody (TfRMAb) to enable brain delivery via BBB TfR-mediated transcytosis. Previously, we found TfRMAb-TNFR to be protective in a mouse model of amyloidosis (APP/PS1) and tauopathy (PS19), and herein we investigated its effects in mice that combine both amyloidosis and tauopathy (3xTg-AD).

Methods

Eight-month-old female 3xTg-AD mice were injected intraperitoneally with …

Limonene Exerts Anti-Inflammatory Effect On Lps-Induced Jejunal Injury In Mice By Inhibiting Nf-Κb/Ap-1 Pathway, Sarmed H. Kathem, Yasameen Sh. Nasrawi, Shihab H. Mutlag, Surya M. Nauli

Pharmacy Faculty Articles and Research

The human gastrointestinal system is a complex ecosystem crucial for well-being. During sepsis-induced gut injury, the integrity of the intestinal barrier can be compromised. Lipopolysaccharide (LPS), an endotoxin from Gram-negative bacteria, disrupts the intestinal barrier, contributing to inflammation and various dysfunctions. The current study explores the protective effects of limonene, a natural compound with diverse biological properties, against LPS-induced jejunal injury in mice. Oral administration of limonene at dosages of 100 and 200 mg/kg was used in the LPS mouse model. The Murine Sepsis Score (MSS) was utilized to evaluate the severity of sepsis, while serum levels of urea and …

The Effects Of Sex Hormones On The Size Of Intestinal Lipoproteins, Andromeda M. Nauli, Ann Phan, Patrick Tso, Surya M. Nauli

Pharmacy Faculty Articles and Research

Larger intestinal lipoproteins are more likely to be retained longer in the intestinal wall, allowing more time for their fat to be hydrolyzed and subsequently taken up by the abdominal viscera. Since men generally accumulate more abdominal visceral fat than women, we sought to determine if males produce larger intestinal lipoproteins compared to females. Using the conscious lymph fistula mouse model, we discovered that the male mice indeed produced larger intestinal lipoproteins than the female mice when they were intraduodenally infused with lipid emulsion. We then employed our differentiated Caco-2 cell model with semipermeable membrane system to determine the effects …

Brain Microvascular Endothelial Cells Possess A Second Cilium That Arises From The Daughter Centriole, Karthikeyan Thirugnanam, Ankan Gupta, Francisco Nunez, Shubhangi Prabhudesai, Amy Y. Pan, Surya M. Nauli, Ramani Ramchandran

Pharmacy Faculty Articles and Research

Primary cilia from the brain microvascular endothelial cells (ECs) are specialized cell-surface organelles involved in mediating sensory perception, cell signaling, and vascular stability. Immunofluorescence (IF) analysis of human primary brain microvascular ECs reveals two cilia per cell. To confirm the in vitro observation of the two-cilia phenotype in human primary brain ECs, ECs isolated from mouse brain were cultured and stained for cilium. Indeed, brain ECs from a ciliopathic mouse (polycystic kidney disease or Pkd2−/−) also possess more than one cilium. Primary cilium emerges from the mother centriole. Centriole analysis by IF suggests that in brain ECs, markers …

Diabetes-Associated Hyperglycemia Causes Rapid-Onset Ocular Surface Damage, Judy Weng, Christopher Ross, Jacob Baker, Saleh Alfuraih, Kiumars Shamloo, Ajay Sharma

Pharmacy Faculty Articles and Research

Purpose: The metabolic alterations due to chronic hyperglycemia are well-known to cause diabetes-associated complications. Short-term hyperglycemia has also been shown to cause many acute changes, including hemodynamic alterations and osmotic, oxidative, and inflammatory stress. The present study was designed to investigate whether diabetes-associated hyperglycemia can cause rapid-onset detrimental effects on the tear film, goblet cells, and glycocalyx and can lead to activation of an inflammatory cascade or cellular stress response in the cornea.

Methods: Mouse models of type 1 and type 2 diabetes were used. Tear film volume, goblet cell number, and corneal glycocalyx area were measured on …

Untargeted Metabolomics Analysis On Kidney Tissues From Mice Reveals Potential Hypoxia Biomarkers, Muhammad Imran Sajid, Francisco J. Nunez, Farideh Amirrad, Moom Rahman Roosan, Tom Vojtko, Scott Mcculloch, Amal Alachkar, Surya M. Nauli

Pharmacy Faculty Articles and Research

Chronic hypoxia may have a huge impact on the cardiovascular and renal systems. Advancements in microscopy, metabolomics, and bioinformatics provide opportunities to identify new biomarkers. In this study, we aimed at elucidating the metabolic alterations in kidney tissues induced by chronic hypoxia using untargeted metabolomic analyses. Reverse phase ultrahigh performance liquid chromatography-mass spectroscopy/mass spectroscopy (RP–UPLC–MS/MS) and hydrophilic interaction liquid chromatography (HILIC)–UPLC–MS/MS methods with positive and negative ion mode electrospray ionization were used for metabolic profiling. The metabolomic profiling revealed an increase in metabolites related to carnitine synthesis and purine metabolism. Additionally, there was a notable increase in bilirubin. Heme, N-acetyl-L-aspartic …

Murine Models Of Graft Versus Host Disease (Gvhd): Focus On Ocular Gvhd, Philipp Steven, Victor L. Perez, Ajay Sharma

Pharmacy Faculty Articles and Research

Graft versus host disease (GVHD) remains a major and serious complication of allogeneic hematopoietic stem cell transplantation. Based on the time of onset, clinical phenotypes, progression kinetics, and pathophysiology, GVHD is stratified into acute, chronic, and overlapping types. The eyes are among the most commonly affected organs in GVHD. Mouse models have played an important role in understanding the several key elements of GVHD pathobiology. The current review discusses the immunology, pathology, and key phenotypic features of mouse models of systemic GVHD. Furthermore, a critical appraisal of mouse models of ocular GVHD (oGVHD) is provided. The disease mechanisms …

Folate Conjugated Nanomedicines For Selective Inhibition Of Mtor Signaling In Polycystic Kidneys At Clinically Relevant Doses, Rajasekharreddy Pala, Ayan K. Barui, Ashraf M. Mohieldin, Jing Zhou, Surya M. Nauli

Pharmacy Faculty Articles and Research

Although rapamycin is a very effective drug for rodents with polycystic kidney disease (PKD), it is not encouraging in the clinical trials due to the suboptimal dosages compelled by the off-target side effects. We here report the generation, characterization, specificity, functionality, pharmacokinetic, pharmacodynamic and toxicology profiles of novel polycystic kidney-specific-targeting nanoparticles (NPs). We formulated folate-conjugated PLGA-PEG NPs, which can be loaded with multiple drugs, including rapamycin (an mTOR inhibitor) and antioxidant 4-hydroxy-TEMPO (a nephroprotective agent). The NPs increased the efficacy, potency and tolerability of rapamycin resulting in an increased survival rate and improved kidney function by decreasing side effects and …

Alcohol As A Modifiable Risk Factor For Alzheimer’S Disease—Evidence From Experimental Studies, Devaraj V. Chandrashekar, Ross A. Steinberg, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by cognitive impairment and memory loss. Epidemiological evidence suggests that heavy alcohol consumption aggravates AD pathology, whereas low alcohol intake may be protective. However, these observations have been inconsistent, and because of methodological discrepancies, the findings remain controversial. Alcohol-feeding studies in AD mice support the notion that high alcohol intake promotes AD, while also hinting that low alcohol doses may be protective against AD. Chronic alcohol feeding to AD mice that delivers alcohol doses sufficient to cause liver injury largely promotes and accelerates AD pathology. The mechanisms by which alcohol can …

Development And Validation Of An Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry Method To Investigate The Plasma Pharmacokinetics Of A KCa2.2/KCa2.3 Positive Allosteric Modulator In Mice, Mohammad Asikur Rahman, Devaraj Venkatapura Chandrashekar, Young-Woo Nam, Basir Syed, David Salehi, Hamidreza Montazeri Aliabadi, Miao Zhang, Reza Mehvar

Pharmacy Faculty Articles and Research

Rationale

There is currently no treatment for spinocerebellar ataxias (SCAs), which are a group of genetic disorders that often cause a lack of coordination, difficulty walking, slurred speech, tremors, and eventually death. Activation of K_Ca2.2/K_Ca2.3 channels reportedly exerts beneficial effects in SCAs. Here, we report the development and validation of an analytical method for quantitating a recently developed positive allosteric modulator of K_Ca2.2/K_Ca2.3 channels (compound 2q) in mouse plasma.

Methods

Mouse plasma samples (10 μL) containing various concentrations of 2q were subjected to protein precipitation in the presence of a structurally similar …

The Effects Of A Blood–Brain Barrier Penetrating Erythropoietin In A Mouse Model Of Tauopathy, Joshua Yang, Weijun Ou, Nataraj Jagadeesan, Juste Simanauskaite, Jiahong Sun, Demi M. Castellanos, David H. Cribbs, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Erythropoietin (EPO), a hematopoietic neurotrophin, is a potential therapeutic for Alzheimer’s disease (AD) but has limited blood–brain barrier (BBB) permeability. EPO fused to a chimeric transferrin receptor monoclonal antibody (cTfRMAb) enters the brain via TfR-mediated transcytosis across the BBB. We previously showed that cTfRMAb-EPO is protective in a mouse model of amyloidosis, but its effects on tauopathy are not known. Given that amyloid and tau pathology are characteristics of AD, the effects of cTfRMAb-EPO were studied in a tauopathy mouse model (PS19). Six-month-old PS19 mice were injected intraperitoneally with either saline (PS19-Saline; n = 9) or cTfRMAb-EPO (PS19-cTfRMAb-EPO, 10 mg/kg; …

Chronic Kidney Disease Promotes Cerebral Microhemorrhage Formation, Chuo Fang, Wei Ling Lau, Jiahong Sun, Rudy Chang, Adrian Vallejo, Donghy Lee, Jihua Liu, Han Liu, Yu-Han Hung, Yitong Zhao, Annlia Paganini-Hill, Rachita K. Sumbria, David H. Cribbs, Mark J. Fisher

Pharmacy Faculty Articles and Research

Background

Chronic kidney disease (CKD) is increasingly recognized as a stroke risk factor, but its exact relationship with cerebrovascular disease is not well-understood. We investigated the development of cerebral small vessel disease using in vivo and in vitro models of CKD.

Methods

CKD was produced in aged C57BL/6J mice using an adenine-induced tubulointerstitial nephritis model. We analyzed brain histology using Prussian blue staining to examine formation of cerebral microhemorrhage (CMH), the hemorrhagic component of small vessel disease and the neuropathological substrate of MRI-demonstrable cerebral microbleeds. In cell culture studies, we examined effects of serum from healthy or CKD patients and …

Loss-Of-Function KCa2.2 Mutations Abolish Channel Activity, Young-Woo Nam, Mohammad Asikur Rahman, Grace Yang, Razan Orfali, Meng Cui, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca²⁺-activated potassium channels subtype 2 (K_Ca2.2, also called SK2) are operated exclusively by a Ca²⁺-calmodulin gating mechanism. Heterozygous genetic mutations of K_Ca2.2 channels have been associated with autosomal dominant neurodevelopmental disorders including cerebellar ataxia and tremor in humans and rodents. Taking advantage of these pathogenic mutations, we performed structure-function studies of the rat K_Ca2.2 channel. No measurable current was detected from HEK293 cells heterologously expressing these pathogenic K_Ca2.2 mutants. When co-expressed with the K_Ca2.2_WT channel, mutations of the pore-lining amino acid residues (I360M, Y362C, G363S …

Effects Of Chronic Cirrhosis Induced By Intraperitoneal Thioacetamide Injection On The Protein Content And Michaelis–Menten Kinetics Of Cytochrome P450 Enzymes In The Rat Liver Microsomes, Devaraj Venkatapura Chandrashekar, Barent N. Dubois, Mamunur Rashid, Reza Mehvar

Pharmacy Faculty Articles and Research

Chronic intraperitoneal injection of thioacetamide (TAA) in rats has been used as an animal model of human cirrhosis to study the effects of the disease on drug metabolism. However, TAA inhibits P450 enzymes directly and independently of cirrhosis. We investigated the effects of chronic cirrhosis in rats, induced by 10 weeks of intraperitoneal TAA, on the P450 enzymes after a 10-day washout period to eliminate TAA. Liver histology and serum biomarkers of hepatic function confirmed cirrhosis in all animals. Microsomal total P450 content, P450 reductase activity and ethoxycoumarin O-deethylase activity, a general marker of P450 activity, were significantly reduced by …

Differential Expression And Activities Of Cytochrome P450 3a In The Rat Brain Microsomes And Mitochondria, Nouf Alshammari, Devaraj Venkatapura Chandrashekar, Mamunur Rashid, Reza Mehvar

Pharmacy Faculty Articles and Research

Midazolam (MDZ), a benzodiazepine derivative, is metabolized to 1′- and 4-hydroxylated metabolites (1′-OH-MDZ and 4-OH-MDZ, respectively) by cytochrome P450 3A (CYP3A). The purpose of this study was to investigate the CYP3A-mediated hydroxylation of MDZ in the rat brain mitochondria (MT). Brain microsomes (MC) and MT fractions were prepared from rats (n = 8) using differential and density gradient centrifugations, and the purity of the fractions was evaluated using VDAC1 and calreticulin as markers of MT and MC, respectively. The formation rates of 1′-OH-MDZ and 4-OH-MDZ in the rat brain MC and MT samples were determined using an LC–MS/MS method …