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2.
J Pharmacol Exp Ther ; 338(1): 246-54, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21464335

ABSTRACT

Tamoxifen is a selective estrogen receptor (ER) modulator, but it is also a deactivating ligand for estrogen-related receptor-γ (ERRγ) and a full agonist for the G protein-coupled estrogen receptor (GPER). Fulvestrant is a selective ER down-regulator that lacks agonist effects on ERα/ERß, is inactive on ERRγ, but acts as a full agonist on GPER. Fulvestrant effects on tamoxifen actions on uterine and somatic growth, bone, the growth hormone (GH)-insulin-like growth factor I (IGF-I) axis, and pituitary prolactin were analyzed to pharmacologically discriminate tamoxifen effects that may be mediated by ERα/ERß versus ERRγ versus GPER. Ovariectomized rats received tamoxifen (0.6 mg/kg/daily) plus fulvestrant at 0, 3, 6, or 12 mg/kg/daily for 5 weeks; controls received vehicle or 6 mg/kg fulvestrant daily. Tamoxifen effects to increase uterine weight, decrease serum IGF-I, increase pituitary prolactin, and increase bone mineral density could be fully blocked by fulvestrant, indicating mediation by ERα/ERß. Tamoxifen effects to decrease pituitary GH, tibia length, and body weight were only partially blocked by fulvestrant, indicating involvement of mechanisms unrelated to ERα/ERß. Fulvestrant did not inhibit tamoxifen actions to reduce total pituitary protein, again indicating effects not mediated by ERα/ERß. Tamoxifen actions to reduce serum GH were mimicked rather than inhibited by fulvestrant, pharmacological features consistent with GPER involvement. However, fulvestrant alone increased IGF-I and also blocked tamoxifen-evoked IGF-I decreases; thus fulvestrant effects on serum GH might reflect increased IGF-I feedback inhibition. Fulvestrant alone had no effect on the other parameters. The findings indicate that mechanisms unrelated to ERα/ERß contribute to tamoxifen effects on body weight, bone growth, and pituitary function.


Subject(s)
Bone Development/physiology , Estradiol/analogs & derivatives , Estrogen Receptor alpha/physiology , Estrogen Receptor beta/physiology , Receptors, Estrogen/physiology , Receptors, G-Protein-Coupled/physiology , Tamoxifen/pharmacology , Animals , Bone Density/drug effects , Bone Density/physiology , Bone Development/drug effects , Estradiol/pharmacology , Female , Fulvestrant , Ovariectomy , Pituitary Gland/drug effects , Pituitary Gland/physiology , Random Allocation , Rats , Rats, Sprague-Dawley
5.
Headache ; 46(8): 1230-45, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16942467

ABSTRACT

OBJECTIVES: We examined changes in the serotonin system across the estrous cycle in trigeminal ganglia of female rodents to determine which components are present and which are regulated by the variations in levels of ovarian steroids that occur during the estrous cycle. BACKGROUND: Migraine is 2-3 times more prevalent in women than in men and attacks are often timed with the menstrual cycle, suggesting a mechanistic link with ovarian steroids. Serotonin has been implicated in the pathogenesis of migraine, and the effectiveness of triptans, selective 5HT-1B/D/F agonists, has provided further support for this concept. It is not known whether serotonin, its rate-limiting enzyme tryptophan hydroxylase (TPH), or its receptors are regulated by ovarian steroids in trigeminal ganglia. METHODS: We used reverse transcription-polymerase chain reaction to examine gene expression in cycling mice, Western blots to examine protein expression, double-labeling immunohistochemistry using markers of nociceptors and nonnociceptors and confocal microscopy to identify specific types of neurons, and primary tissue culture to examine effects of estrogen on trigeminal neurons in vitro. RESULTS: In C57/BL6 mice mRNA levels of TPH-1, the rate-limiting enzyme in serotonin synthesis, were over 2-fold higher and protein levels were 1.4-fold higher at proestrus, the high estrogen stage of the cycle than at diestrus, the low estrogen stage. TPH protein also was present in primary trigeminal cultures obtained from female Sprague-Dawley rats, but levels were not affected by 24-hour treatment with physiological levels (10(-9) M) of 17beta-estradiol. Gene expression of 5HT-1B and 5HT-1D receptors in trigeminal ganglia was not regulated by the estrous cycle. Serotonin was present in trigeminal neurons containing CGRP, a potent vasoactive neuropeptide, peripherin, an intermediate filament present in neurons with unmyelinated axons, neurofilament H, which is present in neurons with myelinated axons, and in neurons binding IB4, a marker of nonpeptidergic nociceptors. Serotonin was also present in neurons containing 5HT-1B. The serotonin-positive population was significantly larger in diameter than the serotonin-negative population. Conclusions.-Expression of the rate-limiting enzyme required for serotonin synthesis is regulated during the natural estrous cycle, and serotonin is present in larger trigeminal neurons of all the major subtypes. Colocalization of serotonin with 5HT-1B suggests that this receptor functions as an autoreceptor to regulate serotonin release. Cyclical changes in serotonin levels in trigeminal ganglia could contribute to the pathogenesis of menstrual migraine.


Subject(s)
Estrous Cycle/metabolism , Migraine Disorders/metabolism , Serotonin/metabolism , Trigeminal Ganglion/metabolism , Animals , Blotting, Western , Estradiol/pharmacology , Estrous Cycle/genetics , Female , Gene Expression/drug effects , Immunohistochemistry , Mice , Mice, Inbred C57BL , Migraine Disorders/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptor, Serotonin, 5-HT1B/genetics , Receptor, Serotonin, 5-HT1B/metabolism , Receptor, Serotonin, 5-HT1D/genetics , Receptor, Serotonin, 5-HT1D/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Serotonin/analysis , Tissue Culture Techniques , Trigeminal Ganglion/drug effects , Tryptophan Hydroxylase/genetics , Tryptophan Hydroxylase/metabolism
6.
Neurosci Lett ; 399(3): 220-5, 2006 May 22.
Article in English | MEDLINE | ID: mdl-16497437

ABSTRACT

Human studies of unexplained cerebral palsy (CP) suggest an association with maternal infection. We used an established model of maternal infection, lipopolysaccharide (LPS) administration, to investigate the molecular changes in the fetal brain that may link maternal infection and CP. We compared gene expression in brains from mouse pups exposed to LPS in utero to those from saline-treated controls. Dams were injected with 50 microg LPS or saline on E18 with surgical delivery from 0.5 to 6h later. Differential gene expression was analyzed in the whole mouse brain using RT-PCR. When compared to control mice, pups exposed to LPS showed increased expression of pro-inflammatory genes monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), and interleukin-1beta (IL-1beta), as well as VEGF, a regulator of vascular development and permeability, the anti-apoptotic protein Y-box-binding protein-1 (YB-1), and the neuronal differentiation factor necdin. LPS-exposed mice also showed downregulation of semaphorin 5b and groucho, involved in axon guidance and neurogenesis, respectively, providing evidence that LPS may disrupt normal developmental pathways. These data suggest possible mechanisms for adverse neurological outcomes following maternal infection involving elevated cytokine levels and altered expression of developmental genes in the fetal brain.


Subject(s)
Brain/drug effects , Cytokines/metabolism , Gene Expression/drug effects , Genes, Developmental/drug effects , Prenatal Exposure Delayed Effects , Analysis of Variance , Animals , Brain/embryology , Cytokines/classification , Disease Models, Animal , Embryo, Mammalian , Female , Lipopolysaccharides , Mice , Pregnancy , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods , Time Factors
7.
Neuropeptides ; 40(1): 35-46, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16376425

ABSTRACT

Several disorders mediated by the trigeminal nerve including migraine and temporomandibular disorder (TMD) are more common in women than in men, and painful attacks are often linked to the menstrual cycle. Estrogen receptors in trigeminal neurons may be involved in regulating neuronal function, causing changes in sensitivity that contribute to these attacks. In a previous study, we demonstrated that expression of specific neuropeptides including galanin and neuropeptide Y in trigeminal ganglia of female rodents varies with the estrous cycle. In this study, we examined expression of the orexigenic peptide ghrelin in trigeminal ganglia of cycling female mice. RT-PCR studies demonstrated that ghrelin mRNA is upregulated by over 5-fold at the high estrogen stages of the cycle, proestrus and early estrus over the levels expressed at the low estrogen stage of the cycle, diestrus. Double-labeling immunohistochemical studies and cell size measurements were conducted to identify the phenotype of neurons in trigeminal ganglia containing ghrelin. Ghrelin was present in trigeminal neurons containing peripherin, a marker of neurons with unmyelinated axons, in trigeminal neurons binding IB4, a marker of nonpeptidergic nociceptors, in trigeminal neurons containing neurofilament H, a marker of neurons with myelinated axons, and in trigeminal neurons containing the neuropeptide calcitonin gene-related peptide (CGRP). Ghrelin-positive neurons averaged 25.6 microm in diameter, but included neurons in all the size ranges except the smallest peripherin-positive neurons. Thus, nearly all of the major populations of trigeminal neurons including peptidergic and nonpeptidergic nociceptors contain ghrelin. These studies suggest that ghrelin, a multifunctional peptide, may contribute to the mechanism linking orofacial pain syndromes in females, including temporomandibular disorder and migraine, to cyclical hormonal changes.


Subject(s)
Estrus/physiology , Neurons/physiology , Trigeminal Nerve/physiology , Animals , Base Sequence , DNA Primers , Female , Gene Expression Regulation , Ghrelin , Growth Hormone/physiology , Mice , Mice, Inbred C57BL , Peptide Hormones/genetics , RNA, Messenger/genetics
8.
Neuropeptides ; 39(4): 409-17, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15936815

ABSTRACT

Women are more than three times as likely as men to experience migraine headaches and temporomandibular joint pain, and painful episodes are often linked to the menstrual cycle. To understand how hormone levels may influence head and face pain, we assessed expression of pain-associated neuropeptides and estrogen receptor alpha (ERalpha) during the natural estrous cycle in mice. Gene expression was analyzed in the trigeminal ganglia of cycling female mice at proestrus, estrus and diestrus using RT-PCR. Peptide/protein expression in trigeminal neurons was analyzed using immunohistochemistry. ERalpha mRNA was present at all stages and highest at estrus. ERalpha protein was present in the cytoplasm of medium-sized and small trigeminal neurons. ERalpha immunoreactive neurons were most common at diestrus. CGRP and ANP mRNAs did not change across the estrous cycle, while expression of galanin and NPY mRNAs were strongly linked to the estrous cycle. Galanin mRNA levels peaked at proestrus, when expression was 8.7-fold higher than the diestrus levels. Galanin immunoreactivity also peaked at proestrus. At proestrus, 7.5% of trigeminal neurons contained galanin, while at estrus, 6.2% of trigeminal neurons contained galanin, and at diestrus, 4.9% of trigeminal neurons contained galanin. NPY mRNA peaked at estrus, when levels were 4.7-fold higher than at diestrus. Our findings suggest that estrogen receptors in trigeminal neurons modulate nociceptive responses through effects on galanin and NPY. Variations in neuropeptide content in trigeminal neurons across the natural estrous cycle may contribute to increases in painful episodes at particular phases of the menstrual cycle.


Subject(s)
Estrous Cycle/physiology , Facial Pain/physiopathology , Galanin/genetics , Neuropeptide Y/genetics , Trigeminal Ganglion/physiology , Animals , Atrial Natriuretic Factor/genetics , Atrial Natriuretic Factor/metabolism , Calcitonin Gene-Related Peptide/genetics , Calcitonin Gene-Related Peptide/metabolism , Diestrus/physiology , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/metabolism , Estrogens/physiology , Estrus/physiology , Facial Pain/metabolism , Female , Galanin/metabolism , Gene Expression/physiology , Immunohistochemistry , Mice , Mice, Inbred C57BL , Neuropeptide Y/metabolism , Ovary/physiology , Proestrus/physiology , Reverse Transcriptase Polymerase Chain Reaction
9.
Hum Pathol ; 36(4): 439-43, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15892008

ABSTRACT

Extraskeletal osteosarcoma (ESOS) is a rare soft tissue sarcoma, typically characterized by high-grade histological features and a grave prognosis. However, 4 cases of well-differentiated ESOS with a better prognosis have been documented in the literature within the last 40 years. We report 2 additional cases, 1 with multicentric presentation and dedifferentiation, and we emphasize the histological features that are useful in distinguishing this lesion from other soft tissue tumors. Well-differentiated ESOS seems to represent a rare but distinct low-grade variant of ESOS. The limited published experience suggests that although the biologic behavior of this tumor is better than that of classical ESOS, there are cases with progression to a higher grade, leading eventually to final demise.


Subject(s)
Osteosarcoma/pathology , Soft Tissue Neoplasms/pathology , Adult , Back , Cell Differentiation , Female , Follow-Up Studies , Humans , Male , Neoplasm Metastasis , Osteosarcoma/diagnostic imaging , Soft Tissue Neoplasms/diagnostic imaging , Thigh , Tomography, X-Ray Computed
10.
Neurosci Lett ; 369(1): 28-32, 2004 Oct 07.
Article in English | MEDLINE | ID: mdl-15380302

ABSTRACT

Adverse effects of age on the outcome of brain injury are well documented, but the mechanism is not well understood. Enhanced expression of proinflammatory cytokines and chemokines has long been linked to neuronal and glial responses to brain injury. In the present study, we used retrograde degeneration of thalamus as a model for secondary neuron death after cortical injury. We investigated the inflammatory component of glial responses to injury by determining mRNA expression of cytokines (TNF-alpha, IL-6, IL-1beta and IFN-gamma), chemokines (MCP-1 and RANTES) and iNOS in thalamus at day 0, 1, 3 and 7 after visual cortex ablation in mice aged 24 (old) and 4 months (young). Old mice demonstrated higher basal expression of TNF-alpha, IL-6, IL-1beta, MCP-1, RANTES and iNOS than young mice, while basal IFN-gamma expression was lower in the brains of older mice. Following injury, thalami of old mice demonstrated higher gene expression of TNF-alpha, IL-1beta, MCP-1, RANTES, and iNOS than young mice. Maximal expression of these five genes was observed 1 day following injury. IL-6 showed maximal gene expression 3 days after injury. By contrast, the increases in IFN-gamma expression after injury were smaller in old than in young mice. Our data demonstrate that both the baseline levels and the responses to injury of specific inflammatory molecules increase during aging. The increased expression of these critical molecules in inflammatory cascades may be responsible for increased secondary neuron death after injury in aging brain, suggesting that strategies to reduce these age-specific differences may help in the development of specific targets for pharmacologic intervention for the aging population.


Subject(s)
Brain Injuries/metabolism , Chemokines/metabolism , Cytokines/metabolism , Gene Expression/physiology , Neurons/metabolism , Age Factors , Animals , Brain Injuries/complications , Brain Injuries/genetics , Cell Death/physiology , Chemokines/genetics , Cytokines/genetics , Male , Mice , Mice, Inbred C57BL , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods , Thalamus/cytology , Thalamus/metabolism , Time Factors
11.
J Am Osteopath Assoc ; 104(6 Suppl 6): S2-8, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15222639

ABSTRACT

Because patients with major psychiatric illnesses increasingly are treated first--and sometimes exclusively--by primary care physicians, improved diagnostic skills and knowledge of treatment options are essential to improved patient outcomes and quality of life. This article reviews the incidence of bipolar disorder and burdens associated with misdiagnosis of the illness. It also emphasizes the evaluation and recognition of bipolar disorders to assist physicians in making accurate diagnoses, as well as reviewing the pharmacologic options used in treatment.


Subject(s)
Bipolar Disorder/diagnosis , Bipolar Disorder/drug therapy , Primary Health Care , Antimanic Agents/therapeutic use , Antipsychotic Agents/therapeutic use , Benzodiazepines/therapeutic use , Diagnostic Errors , Humans , Lamotrigine , Lithium/therapeutic use , Olanzapine , Triazines/therapeutic use , Valproic Acid/therapeutic use
12.
Brain Res Mol Brain Res ; 126(1): 57-66, 2004 Jul 05.
Article in English | MEDLINE | ID: mdl-15207916

ABSTRACT

Oligemia is blood flow reduction without acute tissue damage that occurs in shock, migraine, and stroke penumbra. We developed a mouse model of oligemia by lowering mean arterial pressure to 30-40 mm Hg, resulting in a 50% reduction in cerebral blood flow as measured by laser Doppler, and reperfusing the blood after 30 min. Control experiments included anesthesia-only and surgery without blood withdrawal. Using immunohistochemistry, we localized the transcription factors Nrf2, which regulates expression of antioxidant and detoxification protein, and c-Fos, a marker of neuronal activation. Nrf2 was found only in oligemia mice and was localized in neurons of the cingulate cortex and cerebellar Purkinje cells. By contrast, c-Fos was found widely expressed in both groups and was localized in neurons in regions associated with response to stress, immunomodulation, and fluid homeostasis, including the periaqueductal gray and periventricular nucleus. These data indicate that c-Fos expression occurs as a result of surgical stress, but Nrf-2 upregulation is specific to oligemia. The CLONTECH Atlas 1.2 Mouse Array was used to assess genes that were up or down-regulated in oligemia versus surgery controls. Of 1176 genes, 29 differed between oligemia and surgery groups. Upregulation of oxidative stress induced (OSI) protein, heat shock protein (HSP) 84 and transthyretin (TTR) precursor in the oligemia group was confirmed with RT-PCR. The expression of HSP 84, transthyretin precursor, and OSI genes adds further evidence that oligemia induces an oxidative stress response in the brain.


Subject(s)
Brain/physiology , Cerebrovascular Circulation/physiology , DNA-Binding Proteins/metabolism , Gene Expression Profiling , Proto-Oncogene Proteins c-fos/metabolism , Trans-Activators/metabolism , Animals , Brain/blood supply , Brain/surgery , Gene Expression Regulation , Laser-Doppler Flowmetry , Male , Mice , Mice, Inbred C57BL , NF-E2-Related Factor 2 , Neurons/cytology , Neurons/metabolism , Oligonucleotide Array Sequence Analysis , Oxidative Stress , Regional Blood Flow
13.
J Androl ; 25(4): 523-34, 2004.
Article in English | MEDLINE | ID: mdl-15223841

ABSTRACT

Testis dysfunction can weaken bone and reduce muscle mass as well as impair sexual function. Testosterone (T) therapy has useful effects on sex organs, bone, and muscle in T-deficient males, but prostate concerns can preclude T use in some men. Although estrogens or other drugs can protect bone in men, gynecomastia makes estrogens unappealing, and other drugs may also be undesirable in some cases. Selective estrogen receptor modulators (SERMs) inhibit estrogen-evoked sex organ growth but mimic estrogen effects on bone and cholesterol and are advantageous for some women. SERMs may also be useful in men who must avoid androgens. As a preclinical test of this idea, tamoxifen (a SERM) and testosterone propionate (TP, a classic androgen) were compared for their efficacy in preventing varied effects of orchidectomy (ORX) in adult male rats. ORX led to ventral prostate and seminal vesicle atrophy and decreases in somatic growth, proximal tibia bone mineral density (BMD), and serum growth hormone (GH) and insulin-like growth factor I (IGF-I). ORX also increased anterior pituitary glandular kallikrein, serum cholesterol, and body temperature. Pituitary prolactin (PRL) content was unaltered. ORX effects on sex organs, somatic growth, IGF-I, cholesterol, body temperature, and pituitary kallikrein were prevented by TP at 1 mg/kg (3 doses per week), but BMD and GH were unresponsive. ORX effects on BMD and GH were prevented by TP at 10 mg/kg, but this dose evoked supraphysiologic increases in sex organs and PRL, failed to restore somatic growth, and further reduced IGF-I. Tamoxifen (1 mg/kg daily) prevented ORX effects on BMD, GH, and cholesterol without altering basal or TP-induced sex organ growth and further reduced IGF-I and somatic growth. Tamoxifen did not alter basal PRL but blocked increases caused by TP at 10 mg/kg. In summary, tamoxifen prevented ORX effects on bone and cholesterol in male rats without affecting sex organs or PRL and might be useful for men who must avoid androgens. Unexpectedly, a TP dose that replicated testis effects on sex organs and other targets had no effect on BMD or GH, and a larger TP dose that restored BMD and GH was worse at replicating normal male physiology. In addition, correlation/regression results suggested that the GH-IGF-I axis contributes to changes in BMD.


Subject(s)
Genitalia, Male/physiology , Growth Hormone/physiology , Insulin-Like Growth Factor I/physiology , Orchiectomy , Tamoxifen/pharmacology , Testosterone Propionate/pharmacology , Animals , Bone Density/drug effects , Genitalia, Male/drug effects , Genitalia, Male/growth & development , Male , Rats
14.
South Med J ; 96(8): 824-7, 2003 Aug.
Article in English | MEDLINE | ID: mdl-14515930

ABSTRACT

Hypothyroidism is a common condition. Rarely, it may occur in combination with autoimmune failure of other endocrine glands (autoimmune polyendocrinopathy syndrome type 2, previously known as Schmidt's syndrome). In such cases, restoring normal thyroid function may precipitate adrenal failure. Clinicians should have a high index of suspicion for this condition in patients with Addison's disease, those with a family history of autoimmune endocrine gland failure, patients with one autoimmune endocrine disease who develop nonspecific or serious illness, and patients with type 1 diabetes mellitus whose insulin requirements drop without obvious explanation.


Subject(s)
Addison Disease/etiology , Hormone Replacement Therapy/adverse effects , Hypothyroidism/complications , Hypothyroidism/drug therapy , Iodide Peroxidase , Iron-Binding Proteins , Polyendocrinopathies, Autoimmune/complications , Polyendocrinopathies, Autoimmune/drug therapy , Thyroxine/adverse effects , Addison Disease/diagnosis , Addison Disease/drug therapy , Adrenocorticotropic Hormone , Adult , Autoantibodies/blood , Autoantigens/immunology , B-Lymphocytes/immunology , Diagnosis, Differential , Drug Monitoring , Female , Hormone Replacement Therapy/methods , Humans , Hydrocortisone/blood , Hypothyroidism/diagnosis , Hypothyroidism/immunology , Male , Polyendocrinopathies, Autoimmune/diagnosis , Polyendocrinopathies, Autoimmune/immunology , Precipitating Factors , T-Lymphocytes/immunology , Thyrotropin/blood , Thyroxine/blood , Weight Loss
15.
Acad Med ; 77(11): 1173-4, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12431955

ABSTRACT

OBJECTIVE: (1) To integrate clinical problem solving into freshman cell and tissue biology (CTB) and (2) to enhance understanding of diabetes using CTB principles to explain the etiology, management, and development of complications in terms of cell, tissue, and organ structure and function. DESCRIPTION: First-year medical students often question the need to learn detailed basic science material. Although clinical content has increased throughout basic science courses, little attempt has been made to link clinical correlations to one another or to enhance use of basic science material in clinical problem solving. The CTB course applies pertinent cell biology concepts such as cell proliferation, differentiation, migration, adhesion, and morphogenesis to tissue and organ function. Diabetes mellitus was chosen as a theme for CTB as diabetes has devastating effects on multiple tissues, and the disease has reached epidemic proportions in the United States, affecting individuals of every age and population group. Type I diabetes, presenting as ketoacidosis in a ten-year-old boy, was introduced by generalist physicians using a "grand rounds" approach. This format challenged students on the first day of medical school to diagnose a patient's problem and to explain the clinical findings in terms of anatomic, biochemical, and physiologic changes. The role of the blood/bicarbonate buffering system was the main focus of faculty-led discussion. The patient was then presented at age 25 with many diabetic complications. This stimulated discussion of the etiology of diabetes (type I versus type II), glycation, and the use of hemoglobin (Hb) A1c to monitor blood sugar control. Compliance and other aspects of diabetes management were added to the discussion. Faculty provided scientific information as necessary, and summary materials were distributed after the sessions. The interaction of a cell biologist with two generalist physicians optimized the integration of basic science with clinical problem solving. During the two semesters of CTB, the diabetes case is frequently referenced. Insulin synthesis provides the model for protein synthesis. Glycation, advanced glycation end products (AGE), and receptors (RAGE) are discussed. Other diabetes-related topics include wound healing (epithelium), basement membrane thickening (connective tissue), insulin regulation of muscle metabolism, diabetic neuropathy (neurohistology), platelet adhesiveness, glycation and HbA1c (blood), osteoporosis and Charcot joints (skeletal system), autoimmune mechanisms (cellular immunology), atherosclerosis and high blood pressure (blood vessels), diabetic nephropathy (renal), altered hepatic and gastrointestinal function, impotence (male reproductive system), and a comparison of type I and type II diabetes (endocrine system). DISCUSSION: Students have provided very positive feedback. The initial case enhanced interest in CTB, established clinical relevance, and has motivated learning and integration of materials from different parts of CTB and other courses. Other courses are now formally linking to the theme. For example, neuroscience will revisit diabetic neuropathy and retinopathy, physiology will relate ketoacidosis to acid-base balance, a human anatomy clinical correlation is being designed for transplantation surgeons to "cure" our diabetic patient with a renal-pancreas transplant. Uses of the case for introduction to clinical medicine, aspects of medical ethics, preventive medicine, and courses in pharmacology and pathology are contemplated.


Subject(s)
Biology/education , Clinical Medicine/education , Education, Medical, Undergraduate/methods , Child , Diabetes Mellitus, Type 2/physiopathology , Diabetes Mellitus, Type 2/therapy , Humans , Male
16.
Kidney Int ; 62(5): 1560-9, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12371956

ABSTRACT

BACKGROUND: BALB/c mice homozygous for the cpk mutation develop a form of polycystic kidney disease (PKD) with multiorgan pathology similar to human autosomal recessive PKD. Messenger RNA expression in multiple affected organs was analyzed to determine if common gene cascades were misexpressed in the cystic kidney and extrarenal sites of disease. In cystic kidneys, misexpressed mRNAs were found in one of four general groups: proliferation/cell growth, apoptosis, differentiation or extracellular matrix. METHODS: RNA was isolated from kidney, liver and pancreas of cystic and normal BALB/c-cpk mice. Using Northern blot hybridization and ribonuclease protection assays (RPA), the expression of several genes thought to be associated with PKD, namely c-myc, epidermal growth factor receptor (EGF-R) and PKD-1, were evaluated. RPAs were used to assess mRNA expression of cyclins and members of the bax/bcl-2 family. In addition, kidney, liver and pancreas were immunostained for c-Myc and PCNA. RESULTS: Cystic kidney, liver and pancreas all exhibited similar patterns of mRNA misexpression of c-myc, EGF-R and PKD-1. In addition, a number of cell proliferation and apoptosis-related mRNAs also were elevated in cystic kidney and pancreas. Renal epithelial cells expressing proliferation-associated proteins [c-Myc and proliferating cell nuclear antigen (PCNA)] were nearly absent in normal kidney; however, cells of cystic and non-cystic renal tubules plus liver and pancreatic cyst exhibited an increased number of nuclei labeled with antibodies to these proteins. CONCLUSIONS: These data suggest that similar pathologic mechanisms (including the expression of c-myc, EGF-R, PKD-1, cyclin, and bax/bcl-2 family mRNAs) may be responsible for the development of cystic changes in kidney, liver and pancreas in murine autosomal recessive PKD. Treatments targeting these similarly misexpressed mRNAs may be efficacious in ameliorating the cystic pathology in the kidney as well as the other affected organs in ARPKD.


Subject(s)
Polycystic Kidney, Autosomal Recessive , RNA, Messenger/genetics , Animals , Apoptosis , Disease Models, Animal , ErbB Receptors/genetics , Female , Gene Expression , Kidney/chemistry , Kidney/pathology , Kidney/physiology , Liver/pathology , Liver/physiology , Male , Mice , Mice, Inbred BALB C , Mice, Mutant Strains , Mitosis , Pancreas/pathology , Pancreas/physiology , Polycystic Kidney, Autosomal Recessive/genetics , Polycystic Kidney, Autosomal Recessive/pathology , Polycystic Kidney, Autosomal Recessive/physiopathology , Proliferating Cell Nuclear Antigen/analysis , Proteins/genetics , Proto-Oncogene Proteins c-myc/genetics , TRPP Cation Channels
17.
Brain Res Mol Brain Res ; 103(1-2): 12-27, 2002 Jun 30.
Article in English | MEDLINE | ID: mdl-12106688

ABSTRACT

The mechanisms regulating retrograde neuronal degeneration and subsequent death of thalamic neurons following cortical injury are not well understood. However, the delay in the onset of retrograde cell death and observed morphological changes are consistent with apoptosis. Our previous studies demonstrated that monocyte chemoattractant protein-1 (MCP-1), a beta-chemokine that attracts cells of monocytic origin to sites of injury, is rapidly and specifically expressed in the lateral geniculate nucleus following visual cortical lesions. To determine the potential role of MCP-1 in retrograde degeneration, the present study examined the effect of genetic deletion of MCP-1 (MCP-1 KO or -/-) or its high affinity receptor CCR2 (CCR2 KO or -/-) on thalamic microglial activation and neuronal cell death following aspiration lesions of the visual cortex in adult mice. Deletion of the MCP-1 gene delayed microglial activation and transiently improved the survival of thalamic neurons. Deletion of the CCR2 receptor resulted in a significant increase in apoptosis as measured by nucleosomal fragmentation after injury compared to wild-type mice, but did not alter neuron survival, suggesting that glial apoptosis is increased in the receptor knockout mice. Investigation of Bcl-2, Bax, Fas, Fas ligand (FasL) and activated caspase-3, key regulators of apoptosis that can be modulated by cytokines, revealed complex alterations of mRNA and protein levels in MCP-1(-/-) and CCR2(-/-) mice. As examples, Bcl-2 protein was detected in wild-type, but not in MCP-1(-/-) mice. Caspase-3 activity was higher in MCP-1(-/-) mice compared to wild-type and CCR2(-/-) mice at 5 days after injury. High levels of activated caspase-3 correlate with the beginning of a period of delayed, but rapid cell death in the thalami of MCP-1(-/-) mice. In summary, our data strongly suggest that MCP-1 is involved in early microglial response to axotomy and that modulation of this chemokine could provide a novel strategy for improved neuronal survival following injury to the central nervous system.


Subject(s)
Chemokine CCL2/genetics , Microglia/pathology , Nerve Degeneration/physiopathology , Thalamus/pathology , Animals , Apoptosis/genetics , Apoptosis/physiology , Caspase 3 , Caspases/metabolism , Cell Survival/genetics , Cell Survival/physiology , Female , Gene Expression/genetics , Gene Expression/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Microglia/physiology , Microsomes/physiology , Nerve Degeneration/pathology , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-bcl-2/genetics , Receptors, CCR2 , Receptors, Chemokine/genetics , Up-Regulation/genetics , Up-Regulation/physiology , bcl-2-Associated X Protein , fas Receptor/genetics
18.
Am Fam Physician ; 65(9): 1845-50, 2002 May 01.
Article in English | MEDLINE | ID: mdl-12018807

ABSTRACT

Persons with lactose intolerance are unable to digest significant amounts of lactose because of a genetically inadequate amount of the enzyme lactase. Common symptoms include abdominal pain and bloating, excessive flatus, and watery stool following the ingestion of foods containing lactose. Lactase deficiency is present in up to 15 percent of persons of northern European descent, up to 80 percent of blacks and Latinos, and up to 100 percent of American Indians and Asians. A sizable number of adults believe they are lactose intolerant but do not actually have impaired lactose digestion, and some persons with lactase deficiency can tolerate moderate amounts of ingested lactose. A diagnosis of lactose intolerance can usually be made with a careful history supported by dietary manipulation. If necessary, diagnosis can be confirmed by using a breath hydrogen or lactose tolerance test. Treatment consists primarily of avoiding lactose-containing foods. Lactase enzyme supplements may be helpful. The degree of lactose malabsorption varies greatly among patients with lactose intolerance, but most of them can ingest up to 12 oz of milk daily without symptoms. Lactose-intolerant patients must ensure adequate calcium intake.


Subject(s)
Lactose Intolerance/diagnosis , Lactose Intolerance/therapy , Calcium, Dietary/administration & dosage , Family Practice , Humans , Lactase , Lactose Intolerance/diet therapy , beta-Galactosidase/therapeutic use
19.
Ann Neurol ; 51(4): 499-506, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11921056

ABSTRACT

Cortical spreading depression (CSD) may be the underlying mechanism of migraine aura. The role of CSD in initiating a migraine headache remains to be determined, but it might involve specific changes in gene expression in the brain. To examine these changes, four episodes of CSD at 5-minute intervals were induced in the mouse brain by application of 300mM KCl, and gene expression was examined 2 hours later using cDNA array and reverse transcriptase-polymerase chain reaction. Controls consisted of groups that received anesthesia only, attachment of recording electrodes only, and application of 0.9% NaCl. Of the over 1,180 genes examined in our experiments, those consistently regulated by CSD included vasoactive peptides; the vasodilator atrial natriuretic peptide was induced by CSD, while the vasoconstrictor neuropeptide Y was downregulated. Other genes specifically regulated by CSD were involved in oxidative stress responses (major prion protein, glutathione-S-transferase-5, and apolipoprotein E). L-type calcium channel mRNA was upregulated. In summary, CSD regulates genes that are intrinsic to its propagation, that identify accompanying vascular responses as a potential source of pain, and that protect against its potential pathological consequences. We believe these observations have strong relevance to the mechanisms of migraine and its outcomes.


Subject(s)
Cortical Spreading Depression/genetics , Migraine Disorders/genetics , Migraine Disorders/physiopathology , Anesthetics , Animals , Apolipoproteins E/genetics , Atrial Natriuretic Factor/genetics , Brain/physiology , Brain/surgery , Brain Chemistry/genetics , Calcium Channels, L-Type/genetics , Cytokines/genetics , Gene Expression/drug effects , Gene Expression/physiology , Glutathione Transferase/genetics , Mice , Models, Animal , Neuropeptide Y/genetics , Oligonucleotide Array Sequence Analysis , Prions/genetics , RNA, Messenger/analysis , Receptors, N-Methyl-D-Aspartate/genetics , Reverse Transcriptase Polymerase Chain Reaction
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